* Refactoring
* Fix upgrade script
* Fix owncloud migration + new helper ynh_handle_app_migration
* Add more informations about ynh_handle_app_migration
* Fix typos, enhance comments, fix spacing
* Rename $dependencies to $pkg_dependencies as matter of homogeneity with other apps
* [enh] Change the label during the migration
ownCloud 9.0 comes with improved occ which allows to install easily from
the command-line. This install rewrite uses those new facilities and also uses
the config:import command to set system and LDAP configuration.