Added license property to GladeProject.
It gets saved as part of the first comment.
Added glade_command_set_project_license() and glade_command_set_project_resource_path() functions.
Implemented them using a common GladeCommandProperty class with let you manipuate any GladeProject
property class
Added License textview to GladeProjectProperties to edit newlly added license property.
Added css-provider-path property
Set style classes on runtime objects
Made glade-previewer monitor css file and display parsing errors in a GtkInfoBar.
Created new GladePreviewWindow widget and lots of cleanups.
Improved screenshot option, save screenshots in any GdkPixbuf supported format.
Added options to take vector screenshots (F5 svg, F6 ps, F7 pdf) and F8 png
Added project css property support
Added --slideshow option

Make --screenshot and --slideshow save every widget in a different page if the format supports it
(like pdf)
glade-previewer: added support for widget templates