Merge pull request #69 from Jon0/master

epic: basic action stack, and a unit moving around.
convert: split up game specification code generation
Merge pull request #155 from TheJJ/convert-splitup

convert: split up game specification code generation
release: new minor release achieved

now supports walking units!
convert: fixed function imports from util module

sound conversion was broken because of that.
reference system to stop segfault when gather target is removed