Merge branch 'guillaume'
* Added the 'getChildAt()' method in the def file
* Fixed Enchant test
* FIx: added nullable to GtkAccelKey in def file of GtkAccelMap lookup_entry method to prevent rising nullpointers from within jg
* Exposed the method guessLanguage(String, String) in LanguageManager
* Exposed the WindowState 'FOCUSED' which may otherwise cause problems when retrieving window states such as maximized.
* Exposed the getChildAt(int, int) method in Grid
* Exposed the queryTooltip interface to connect with the widget. Which in turn also exposed the matching connect method.
* Exposed and documented Tooltip class. Not all methods are exposed. Only those which I find relevant for the class.
* Fix a rename on the queryTooltip to QueryTooltip as it should.
* Added all the methods for the tooltips for a TreeView.
* Took the exampleTooltip file and extended with custom tooltips.
* Treeview tooltip example now added
* FInal changes to the treeview tooltips example
Code formatting

Run code formatter on 'tooltips' branch.
Update AUTHORS
Minor stylistic updates
Merge branch 'tooltips'
Update build infrastructure for Arch Linux
Drop source,target 1.6 from Arch