Lots of fixes, improvements

Added copying of welcome token to clipboard
Added a 'Loading' spinner
Added minor Import improvements
Added optional email address fetching from OpenID (Google ignores it)
Split various crawler classes into separate files
Fixed various issues with Rss and Atom parsers (Blogger's feeds now
appear, RSS1 support also fixes issues with The Oatmeal)
Cleanup and bug fixes
Added a semi-decent README