GtkEntry reshuffling
This branch
- makes GtkEditable useful
- breaks out GtkText from GtkEntry
- uses GtkText in GtkEntry, GtkSpinButton, GtkSearchEntry
- implements GtkEditable in GtkEntry, GtkSpinButton, GtkSearchEntry
- adds a GtkPasswordEntry that also uses GtkText and implements GtkEditable
There is some fallout from the search entry changes in tests and demos, but most things work.
I've left redundant entry and spinbutton apis in place for now - we could remove that if we decide that people should use the editable api for what it covers.
Edited by Matthias Clasen