use custom default gravatar for users without one
add link to change gravatar image on user profile page
don't drop menu down when clicking user name/gravatar; only drop-down when button next to them is clicked
make gravatar/username link in user menu point to dashboard
Handle explicit full-path redirects. Fixes #964.
Include GitHub Import button
Merge pull request #969 from jaspeers/pulldown-menu

Pulldown menu
Clean up profile page design
Fix button