Ajaxify the member's notifications screens

[imath]

• Add a search field,
• too bad we can't use a select box to filter by type...

[imath]

The commit above is making sure existing features for the notifications screen are available in BP Nouveau, and add some features:

• It's now possible to search in notifications
• It's now possible to filter notifications by type (component action)
• The loop is now ajax loaded and all the above actions and the sort one are using ajax.
• The sort action is now inside the Date Received column header.
• Bulk, delete and Mark read or unread are not handled in Javascript because of the pagination.

Here's a preview of how looks the notifications screen now:

I've edited the main buddypress-nouveau.js file, so it would be great to test and make sure no regressions were introduced for the other components.

[robmcclel]

Sweet!

[hnla]

Closing.