Feature/inline edit

Basic implementation of inline edits for text strings. One implemented, you simply click the string you wish to update and it becomes an editable text box, which updates locally and remotely on blur.

You can allow inline updates for the field by passing it an `edit` value:

    { fields: [
        { key: 'name', label: 'Name', edit: Meteor.users },
    ] }

This accepts a Meteor collection, and currently only allows the updating of strings.

Current Drawbacks:
* Not compatible with (is ignored if) tmpl fields, but works out of the box with strings.
* Currently implemented by passing a Meteor.collection into the field, due not being able to call collection.update from the cursor/array alone. If you can think of a better way of doing this let me know.

I also updated the readme