user: remove make local feature

we discussed a bit on what this does and it's confusing as it stands:

* Use case of this is lost in the realms of time
* Possible guess by is that it was to move users of different Cloudron to a central cloudron
* Currently, the design is a bit flawed because the make user local button doesn’t pin the user. The state is lost in next synchronization.
* Maybe, one should use export/import user for this use case
* Let’s disable this button for now, feature is not complete.

src/routes/users.js

@@ -10,7 +10,6 @@ exports = module.exports = {
     verifyPassword,
     setGroups,
     setGhost,
-    makeLocal,
 
     getPasswordResetLink,
     sendPasswordResetEmail,
@@ -204,22 +203,6 @@ async function setPassword(req, res, next) {
     next(new HttpSuccess(204));
 }
 
-async function makeLocal(req, res, next) {
-    assert.strictEqual(typeof req.resource, 'object');
-
-    if (users.compareRoles(req.user.role, req.resource.role) < 0) return next(new HttpError(403, `role '${req.resource.role}' is required but user has only '${req.user.role}'`));
-
-    if (req.resource.source === '') return next(new HttpError(409, 'user is already local'));
-
-    let [error] = await safe(users.update(req.resource, { source: '', inviteToken: '' }, AuditSource.fromRequest(req)));
-    if (error) return next(BoxError.toHttpError(error));
-
-    [error] = await safe(users.sendPasswordResetEmail(req.resource, req.resource.fallbackEmail || req.resource.email, AuditSource.fromRequest(req)));
-    if (error)  return next(BoxError.toHttpError(error));
-
-    next(new HttpSuccess(204, {}));
-}
-
 // This will always return a reset link, if none is set or expired a new one will be created
 async function getPasswordResetLink(req, res, next) {
     assert.strictEqual(typeof req.resource, 'object');