Add convenience GtkTreeViewColumn constructor and tests
Add GtkTreeStore and GtkTreeSelection + further methods
Add several cell renderer
Add GtkCellRenderer and use its interface
Fix GtkListStore constructor, introduce interface GtkTreeModelI
fix tests
fix wrong indexing in list and tree store
GtkTreeStore now working. Added example in tests
incorperate comments of Jameson
Remove GtkTreeModel from generator script
Add remaining types from the tree/list gtk section. Not fully implemented yet
uncomment type definitions until code gen is run
Merge branch 'listView' of github.com:tknopp/Gtk.jl

Also fix end-of-line spaces.

Conflicts:
	src/Gtk.jl
update gbox methods more
improve gtk get method detection algorithm