[Vala] gtk widget bindings complete

[Sam Liddicott <sam liddicott com>]

Thanks to Nicolas who helped convert these to use gtkbuilder.

New files and a sample project are uploaded to:
http://www.liddicott.com/~sam/?p=98

All .glade files can be converted to .ui files
All .ui files can be converted to .vala files
and, as normal, .vala files are converted to .c and .h files and compiled.

The conversions only occur if they are needed according to makefile
inferences, which means if you add demo.glade to the
project_GLADESOURCES you probably also want to add demo.vala (the file
won't exist yet) to project_VALASOURCES

I use stamp files for .glade and .ui files even though I don't need to,
because thats what anjuta uses to group source files, otherwise I had to
search through OTHER to edit my glade files.

Sam