User settings

This is a pull request for issues #455 and #456.

There is no reason to use `form` in `form#set-password`. ID-based selector already uniquely globally identifies the field. In fact. I think that using ids is not a good idea at all. I know that Meteor is using this, but this can break things when you later on include in some other situation two templates with conflicting IDs. We are not really using IDs anywhere, classes are better. (Yes, Meteor is using them, but they have issues because of that, you cannot have two sing-in buttons/forms on a page at the same time.)