read-only database support via decorator (#1441)

New @use_readonly_database decorator will set an override so that that
view will use the readonly DB.  New optional "readonly" database stanza.
Merge branch 'master' of github.com:Stanford-Online/class2go into sef-1441-db-router
database.py template for readonly db, fix typo (#1441)
Fixed to pick up site specific styles

Fixed to pick up site specific styles
Remove redundant warning related to issue #1044

Not sure if this can be closed but the video page already gives a
noscript warning - removed the redundant warning that shows up
temporarily even when you have javascript enabled
added navbar clock
ajax updating navbar clock
Revert "ajax updating navbar clock"

This reverts commit 4d99e492c9355f0f797cfbc79bff7248abfa294f.
Merge remote-tracking branch 'origin' into sef-1441-db-router
Revert "added navbar clock"

This reverts commit 617f5c9c080a7cc5f2c58e174b645a15beba9a54.
Merge branch 'master' of https://github.com/Stanford-Online/class2go
ajax updating navbar clock
removing the console.log lines of code...
refactor fake_remote_grader, use context manager (#1730)

In order to support other kinds of remote grader failure modes, useful
to abstract that functionality into something more general.  Created an
abstract base class (by convention only).

Implement this as a context manager to ensure that the urllib2 cleanup
happens for me.  Cleaner and more reliable.
interactive tests: factor xml out and share (#1730)
interactive grader tests: three failure modes (#1730)
interactive autograder: retry logic, handle more exceptions (#1730)
interactive autograder: more precise watchword checks (#1730)
Adjust timer JS to make it more concise

	modified:   templates/base.html
Merge branch 'master' of https://github.com/Stanford-Online/class2go into giulio-navbar-clock-1979-2