Allow IconView to be added to ScrolledWindow using add()

IconView has scrolling support, so it shouldn't have to be added using
addWithViewport(). When you use addWithViewport(), the IconView does
not correctly re-flow icons as the ScrolledWindow is resized; it
re-flows when the window is widened, but adds a horizontal scrollbar
when the window is narrowed.

A demo program illustrates this issue: http://pastebin.com/HajMj2uh
Don't break compatibility by failing on addWithViewport(iconView)
Documentation snapshots generation bug.

Disable AT Bridge when taking snapshots for documentation.
The default behaviour fails the snapshots taking by raising an error on headless
systems such as Debian/Ubuntu build chroot.
Merge pull request #5 from respawner/doc-accessibility-bug

Doc accessibility bug
Merge pull request #4 from cathalmcginley/master

Allow IconView to be added to ScrolledWindow using add()
Preliminary work on parsing GIR data to generate .defs files.
New GIR parser that build DefsFile like the current DefsParser does.
Fix parsing when type attribute in C namespace cannot be found.
Add the introspection parser as regular parser (can be disabled).
It still does not generate bindings properly (need some debugging).
Also handle new XOM and Jaxen dependencies for Debian (and its
derivatives) for now.
Code format.
Fix several 'null' values retrieved when parsing.
Revert small paste error.
Namespace override.

Add file to override Introspection namespaces to generate proper Java
packages names.
Add changes to handle namespaces overrides.
Handle .gir files location on Debian based distros.
Remove no longer needed files.
Fix some public API classes to match Introspection data.
More fixes for the public API and remove non-existing things.
More fixes for the public API (no override needed anymore).
More fixes for the public API (pass unicode value when needed).