Added history support for geogit layers.

You can also view feature diffs for merged features, as well as for features in the history.
Added history to feature info box.
Changed some styling, added error dialog.
Added localization support and placeholder Spanish translations
More translations
Added temporary commit message.
Added the ability to remove features.
Refactored the geometry editing panel so that it can be used in other places.
Fixed a problem with the commit message being generated without quotes
Started working on inserting features. Currently a work in progress.
Added number validation to attribute editing, moved layer label to layer metadata.
Fixed a few bugs.
Added export to csv to the history diff.