Implement the register function of OC\ContactsManager
$key is not needed for registering contactsmanager callbacks
Supply the contactsmanager object to the callbacks
camelCase vars in OC\ContactsManager
Merge branch 'master' into contactsmanager-register

Conflicts:
	lib/private/contactsmanager.php
Fix wrong var name
Add a resetadminpass command to console - fix #8248
Make ResetAdminPass to ResetPassword
Back to the future
Add doc, check return-value, fix spacing, require interactive
Merge branch 'master' into contactsmanager-register

Conflicts:
	lib/private/contactsmanager.php
no return on register and unregister
Fixed drag and drop from external files, added tests

- Fixed detection whether the drop zone is inside the currently visible
  table
- Now dragging outside the table does nothing instead of uploading,
  because the user might drop on the sidebar
- Added unit tests for the drop handler
clean up tryRememberLogin and save the timestamp of users last login
Fix dropping files below the table
unit  tests for loginWithCookie()
also test whether hooks work
test hooks also on login
clean up here is superflous, will already be removed by user session
add cli command to check a users last login