ui: tweaks & fixes

[bboyatwork]

As a Clutter user I need to feel the familiarity to Twitter in order to feel confident using it.

• 'Clutter' headline clickable
• Separate meow feed from message area
• Move handle under profile picture
• Change background image / find higher-res

From @science-girl:

• background graphic of kittens should be fixed not
• set handle should be a dialog box that pops up upon opening page
• after setting handle, return to screen to send message

[zippy]