Changes

CMake: USE_PREBUILT_MESA_PACKAGE should only be available on Linux.
 (commit: c9ae355)

cmake/patchcmake.c: make sure it builds fine using GCC/G++ 5.x (#1391).
 (commit: 5a57f41)

Updated our Mesa package (#1391).
 (commit: 2d747ba)

Slight update to our QtWebKit readme file (#1391).
 (commit: 93af7a8)

Updated our QtWebKit package (#1391).
 (commit: ecda324)

Updated our CellML API package (#1391).
 (commit: f250a9f)

Updated our SBML API package (#1391).
 (commit: 23ebd4b)

Updated our SED-ML API package (#1391).
 (commit: 194aa77)

Temporarily disable BioSignalML-related plugins (#1391).
 (commit: 7ff0ff0)

Updated our libigt2 package (#1391).
 (commit: e4ca80b)

Updated our LibXDiff and OAuth packages (#1391).
 (commit: 4225d71)

Updated our OpenSSL package (#1391).
 (commit: e2f1d3a)

Updated our SUNDIALS and zlib packages (#1391).
 (commit: cde844e)

Updated our QScintilla and Qwt packages (#1391).
 (commit: c9ae45e)

Updated our Zinc package (#1391).
 (commit: 00d64b9)

Updated our LLVM+Clang package (#1391).
 (commit: 9cc1901)

Linux: rebuild BioSignalML libraries for GCC 5.5 (#1391).
 (commit: 27cddfe)

QtWebKit package: make sure that our generated CMake files are properly
patched (#1391).
 (commit: 4d824de)

Linux: rebuild BioSignalML libraries for GCC 5.4 (#1391)
 (commit: e079865)

Updated our QtWebKit package (#1391).
 (commit: d623ac9)

Some minor cleaning up (#1391) [ci skip].
 (commit: 8e2e923)

Zinc package: slight update to our tests until we formally upgrade to
Zinc 3.1.2 (#1391) [ci skip].
 (commit: 0a3a16d)

Travis CI: check whether there is an Ubuntu 16.04 LTS machine that we
could use (#1391).
Indeed, we now build everything on Ubuntu 16.04 LTS (Xenial), so to rely
on Ubuntu 14.04 LTS (Trusty) is not really an option anymore (it breaks
things; see https://travis-ci.org/opencor/opencor/jobs/263037249).
 (commit: dbf0b5a)

Updated our SBML and SED-ML API packages (#1391).
Indeed, our SBML API package didn’t have support for bzip2, which we 
need (for our tests, if anything). Now, because our SED-ML API package 
depends on our SBML one, we also updated it just to be on the safe side.
 (commit: d3ba50f)

Travis CI: well, no Ubuntu 16.04 LTS available, so reverting to Ubuntu
14.04 LTS and see what we can do with it (#1391).
See https://travis-ci.org/opencor/opencor/jobs/263072654, although we 
asked for the xenial distribution, Travis CI doesn’t know about it and 
therefore went for its current default distribution, which is trusty.
 (commit: 87eb138)

Travis CI: see whether defining _GLIBCXX_USE_CXX11_ABI=0 makes any
difference (#1391).
 (commit: 6d82c51)

Travis CI: see whether defining _GLIBCXX_USE_CXX11_ABI=0 makes any
difference (#1391).
 (commit: abacefc)

Travis CI: see whether defining _GLIBCXX_USE_CXX11_ABI=1 makes any
difference (#1391).
 (commit: 894b963)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: 4fd0019)

Reverted part of commit abacefc (oops!) (#1391) [ci skip].
 (commit: 557325c)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: b1a9ba3)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: ce24071)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: a10306d)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: 675bbf6)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: 942c13e)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: d098a5d)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: 5c9d6c0)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: fcbdbac)

Some minor cleaning up.
 (commit: 7e88595)

Plugin tests: make sure that their external dependencies are set in the
same way as for their corresponding plugins (#1391).
Who know, that might explain why things don’t work on Travis CI?!
 (commit: 0d5c089)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: c3a3853)

Trying to remove some RPath information on Linux (#1391).
I get the feeling that it might not be needed…
 (commit: 8933481)

Trying to remove some RPath information on Linux (#1391).
 (commit: eb6b618)

Trying to remove some RPath information on Linux (#1391).
 (commit: d1c4545)

Ok, removing some RPath information on Linux wasn't a good idea! (#1391)
 (commit: bc2d8ed)

Some minor cleaning up [ci skip].
 (commit: 0d46c88)

Travis CI: trying not to use GCC/G++ 5.x (#1391).
That really ought not to work!
 (commit: 95f67df)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: a7f7919)

Travis CI: trying not to use GCC/G++ 5.x (#1391).
 (commit: 6254f34)

Travis CI: trying not to use GCC/G++ 5.x (#1391).
 (commit: dabe8ab)

Travis CI: trying not to use GCC/G++ 5.x (#1391).
 (commit: 6ee0d34)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: 227480c)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: 57b0001)

Some minor cleaning up.
 (commit: 4b7fb76)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: 33e11e1)

Travis CI: trying to understand that GCC/G++ issue on Ubuntu (#1391).
 (commit: 8f746aa)

Some minor cleaning up [ci skip].
 (commit: 32e5067)

Travis CI: temporarily (hopefully) disable building and running our
tests on Linux (#1391).
Indeed, to build our tests on Linux keeps failing. It might due to a 
discrepancy between Ubuntu 14.04 LTS (which is used on Travis CI) and 
Ubuntu 16.04 LTS, which we now use for building OpenCOR.
 (commit: ec7d4e6)

Travis CI: temporarily (hopefully) disable building and running our
tests on Linux (#1391).
Indeed, to build our tests on Linux keeps failing. It might due to a 
discrepancy between Ubuntu 14.04 LTS (which is used on Travis CI) and 
Ubuntu 16.04 LTS, which we now use for building OpenCOR.
 (commit: 70e2894)