Fixed cataclysm-launcher to properly open symlinks.

When cataclysm and cataclysm-tiles were symlinked to cataclysm-launcher, both would open the tiles version.

The previous script followed symlinks to cataclysm-launcher, which was used as the target file name instead of cataclysm and cataclysm-tiles.

The script now tries to find the binary with the same name as the symlink, that was executed.

Ping @KA101, I mentioned this a few days ago on IRC.