[gtksourceview] (6 commits) Non-fast-forward update to branch wip/undo-redo

[Sébastien Wilmet <swilmet src gnome org>]

The branch 'wip/undo-redo' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  1adece7... UndoManager: improve doc
  a237a75... UndoManager: update_can_undo_can_redo() utility function
  838d25a... UndoManager: another batch of code clean-up
  8432f38... UndoManager: start a new implementation (not finished)

Commits added to the branch:

  3e30d95... Make sure to NULL terminate text for unowned buffers (*)
  de56d87... Updated Hebrew translation (*)
  efa782b... UndoManager: improve data structure doc (*)
  eba31d2... UndoManager: update_can_undo_can_redo() utility function
  bedc921... UndoManager: another batch of code clean-up
  d9b8065... UndoManager: start a new implementation (not finished)

(*) This commit already existed in another branch; no separate mail sent