Setup Travis CI for autobuild AppImage (portable package for Linux)

[ghost]

When Linux support will be added?

[mrozigor]

You can compile current version on linux. Only problems are missing libX11 and libdl (at least at my OS).

[Milek7]

um, it works on linux for few months already

[ghost]

You can compile current version on linux.

Oh, cool! Then lets setup Travis-CI (using file .travis.yml in the root of master branch) for producing AppImage-package (that is portable binary for near all Linux-based distros)

• https://github.com/appimage/appimagekit
  • https://github.com/probonopd/linuxdeployqt
  • https://github.com/probonopd/uploadtool

@probonopd, are you like train games? Lets make Maszyna-*.AppImage for all Linux gamers! ;-)

[Milek7]

I have mixed experiences with AppImage. I had greater success with statically linking glfw, glew, libsndfile, libpng etc. and dynamically linked libx11/wayland, libgl, libopenal and glibc linked to old symbol names (using glibc_version_header). Then we would have four universal binaries: x86/x86-64 and wayland/x11 (as glfw can't select backend at runtime).
I plan to do it sometime, but of course if somebody does it before either using static/dynamic mix or gets AppImage to work I'm happy to accept PRs.

[probonopd]

Hi @Symbian9 do you want to give it a try using the example at https://github.com/probonopd/linuxdeployqt/#using-linuxdeployqt-with-travis-ci? I'm happy to help in case you are running into unforeseen issues. But I think you should give it a try yourself...

There is even a description on how to send a pull request: https://github.com/probonopd/linuxdeployqt/#sending-pull-requests-on-github