Docs: Multiple upgrading/DB migration related changes

[ci skip]
Fixes Breadcrumbs alignment issues in Chrome* (version 24 or later)
Upgraded jquery.fancybox (version 2.1.4)
Override a:link background inherit property
Updated Fancybox version in README
Revert "Redirecto to the full path, which includes script_name."

This reverts commit ba6d1dda041569a98b3f035359fc2ab73f435641.
API: Remove 'tastypie' from INSTALLED_APPS

Necessary for fixing bug #2894
API: Move API registering to its own module and use a factory
API: Disable API by default
s/.net/.com/
Added missing fancybox overlay image.
Reduce volume of Travis build output

Hundreds of lines of build output passed through Travis JS parsing bring
my browser (at least) to its knees - little of it is interesting or even
relevant, keeping the last 40 lines of stdout for most make targets is
plenty (we keep all of stderr).
Avoid misleading messages about change id 0

Fixes bug 2618
Handle exceptions when there are no changes

If no edits recorded, catch DoesNotExist; treat as latest_change_id = 0
Make 0/None 'modified-since' logic explicit