Additions and improvements for Paid Feature

[marta]

We've made some additions and improvements to Notes!

The Notes feature has been added to two action-taking pages:

• You can now add a Note directly on the Add a friend page - handy if you'd like to mark down where you met them or another name you know them by!
• On the Ban and unban users page (under Account -> Privacy) you can now add a Note, including to a group of users all banned at the same time (so that next year you won't need to ask yourself "hey, why did I ban these guys?")

Other changes:

• When you're viewing your existing Notes they're grayed out; click in a field to activate it to change the text (this page can be found from the header by using Profile -> Manage Notes)
• Changes to editing:
  • When you're going to create a new Note but one already exists, you'll get a warning that you're editing an existing Note
  • You can now delete a note from the "Edit note" pop-up in the hover menu
  • You can now delete notes for multiple selected users on the Manage notes page
  • When you change Notes on "Ban|unban users" page, they can be edited and saved with "Save Changes" button