Implement OSX and Debian installer building for Travis

This implements the cross-platform installer builds using the Travis-CI buildbot, like vanilla currently does. This comes with the following extras:

• Update Linux and Mac icons to Kart
• CMake and package defaults changed for Kart
• Rename srb2home folder from srb2 to srb2kart
• https://git.magicalgirl.moe/STJr/SRB2/merge_requests/378 Fix savegamename being improperly built
• https://git.magicalgirl.moe/STJr/SRB2/merge_requests/379 Apply srb2home path to EXEC, SAVECONFIG, and debugfile
• https://git.magicalgirl.moe/STJr/SRB2/merge_requests/445 Resolve buffer overflow crash when configuring System Menu and GIF controls

Full documentation here. Deployer is set up via environment variables set on your Travis-CI project settings.

If you wanted to do these releases, I have this framework set up on my Kart-Public fork on GitHub already, so you may let me know if you'd like to partner for a future release.

Result

These are built with latest master code using v1.0.1 assets; you'll know whether or not how broken that is... I assume the codebase is not net-compatible with the actual release.

Built from kart-travis-deployer-test.

• Buildbot results: https://travis-ci.org/mazmazz/Kart-Public/builds/475621586
• OSX installer: https://mega.nz/#!Oj5XDS7C!0ED6lTbCOKsiuFR78E4tr0NPT0gpfBI8eyRO06gErQ8
• Debian packages: https://launchpad.net/~mazmazz/+archive/ubuntu/kart-test

For OSX, gamedata is saved to ~/srb2kart.

How to install Debian packages via APT

If using Debian, enter this first:

sudo apt-get install dirmngr
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 9E6D656D78A5D8BE4329B55671B17A95D3E04B64

If using Debian or Ubuntu, do this next:

sudo add-apt-repository ppa:mazmazz/kart-test
sudo apt-get update
sudo apt-get install srb2kart

If your Terminal is missing the “add-apt-repository” command, enter sudo apt-get install software-properties-common

The game is installed in /usr/games/SRB2Kart, with an executable symlink installed in your PATH called srb2kart.

For Linux, game data will be saved to ~/.srb2kart