Miscellaneous fixes.

Update-users now stores looked-up users one more (broke this when refactoring).
Log On (vs Sign Up) now sets cookies and redirects correctly.
Add btn-primary class to buttons.
Add "(beta)" in homepage header.
Log friendships correctly.
Correctly find new log-on-form
Improve enqueueBlocks function signature.
Log off deactivated users automatically.

Also remove unnecessary isAuthenticated function.
Update testing instructions to reflect latest changes.
Merge pull request #53 from jsha/misc-fixes

Misc fixes