add language manager
Merge branch '0.4.0' into languages_admin_ui
add language store
Merge branch '0.4.0' into languages_admin_ui
implement language dialog
add event handling
use language store in labels and notes form
Merge branch '0.4.0' into languages_admin_ui
Merge pull request #121 from OnroerendErfgoed/languages_admin_ui

Languages admin ui