Changes since gtkaml 0.4:
- rewritten to directly generate vala AST nodes
- split into gtkamlc and libgtkaml.so
- *.implicits files renamed to *.markuphints

Features:
- the order of the compiled files doesn't count anymore 
(gtkaml files correctly expose public symbols at parse time, then figure out the privates at resolve time)
- custom creation methods (even with parameters) are allowed, the construct {} is still generated
- 


