Switch to gee-0.8 and use custom struct for vieworder (no HashMap).
Handle source file focus detection completely with MainWindow.

 * Completion provider will crash the app.
 * Newly opened tabs aren't automatically selected.
 * New tabs aren't opened right beside the previous selected tab.
Merge branch 'master' into multiple-buffers

Conflicts:
	src/main.vala
	src/project.vala
Proper implementation of method for all opened views (delegate).
Switch back to gee-1.0.

 * Switch back because Debian currently hasn't gee-0.8 in repository.
   See #695982
 * Project is still and will be compatible to gee-0.8 .
Code cleanup (pushed for LSenf).