Changing estimation UI handling to subscription

Less logic in the view.
Fixing problems with "0" estimation

0 == false prevents the correct CSS class from being added. === fixes it.
Cleaning up binary operators

Use === where possible. Using unary + to convert to int.
Fixing bug where 0 was not recognised as min value

If the minimum estimation was 0, it was not highlighted as the mininum.

Strict comparisons help.
Adding storyTitle as an observable with editableText binding
Adding broadcasting of story title

Update function on the server-side stays object-agnostic, we differentiate
between user estimation data and story data in the client.
Adding broadcasting of story title for new users

The "who is there" event is now additionally responded to with the story
title by all clients. This is totally redundant but works for now.
Ignoring jEdit's .marks files