FIX pc/build.gradle script to be project name independant.
Actually use first arg for display mode.
Remove depreciated methods from GameEngine.
Update SnakeGame to avoid depreciated functions.
FIX Windows ignoring XDG_CONFIG_HOME for settings.

As error message when LcoalAppData is not set suggests, it checks for
XDG_CONFIG_HOME then (if apparently on Windows) for LocalAppData.
Change log level on XDG_* vars
Update tags file.
rm make.cmd
Clean up run scripts to support > 1 demo.

Added run.sh
Edited run.cmd

Works as './run.sh demoname'
Modify name of demo output files.