Long time since my last update, but here I am.
So, new stuff. AppImage is now uploaded by TravisCI. The tricky part: Understanding Library Linkage and the g++ compiler.
Library Linkage, it was a real headache. I modified the project so that there is no need to sudo apt install SDL and GLEW, making it very easy to choose what versions you want to use. If a new one comes out, just edit the Setup.sh.
About this new file. When unpacking the projects always run it. It gets you ready for development. If it detects apt it will install some needed libraries for compiling, such as g++ and cmake, but also some needed for SDL extensions, such as libjpeg-dev and libfreetype6-dev.
It is also in this file that SDL and GLEW are downloaded and installed in the dependencies directory. This follows the way the project is handled in Windows, which I think is cleaner (all in one place, no need for extra things).
Finally the g++ compiler. So for this time around, I tried to test the project in Ubuntu 14.04, which has g++ 4.8.4 that already partially supports c++11. Unfortunately, my code base uses some of the unsupported bits, which makes it impossible to support Ubuntu 14.04 with the default compiler. I'll be supporting 16.04 and newer from now on.