navbar clock icon now tells time according to clock system
removed extraneous font file uploads that I missed before...
Removing debug console messages

* (fixes #2279)
.travis.yml update (experimental chromedriver)

inputting the steps necessary to get chromedriver.
Let's see if it breaks the build.
Update .travis.yml to enable selenium

Testing chromedriver setup by enabling headless selenium tests.
.travis.yml needs to install unzip

Unzip needed for chromedriver unpack.
.travis.yml cleanup of formatting
.travis.yml leaving chromedriver in build dir

We can't copy chromedriver into /usr/local/bin, so let's
add the current working directory to our $PATH.
Travis install chromedriver attempt #3
Merge pull request #2280 from Stanford-Online/jrbl-2279-removing-debug-statements

Removing debug console messages
Restore travis.yml

Undoing the damage I did, restoring build to working order.
adding pointers to c2g intro and sandbox courses
test grader caching (#2050)

Generalizes the failing fake autograder, new mode where it will succeed
n time and then fail.
cache interactive autograder results (fix #2050)

Use our simple filesystem-based cache to store results from the remote
grader.  We only cache for two hours for now, which should still be
useful, but we could consider going longer (days).

The cache key is the entire params structure that includes both the
student submission and the grader parameters (grader name, question
number).  This errs on the side of safety.

Some imports and variable cleanups while I was in here.
remove errant debug stmt (#2050)
added twitter block to class homepage, but it needs to be generalized...
#2207 Show quiz summary (in-line) report rows grey if < 20 students
answered.

Also added a bit of explanation text on the report itself.
Couple of cleanups (#2207)
changed to using 'course_prefix' as part of the twitter handle (eg. @ 'db' class) this should pretty much fix #2247
changing back to hardcoded twitter handle, will revisit later with input from @jinpa and others (#2247)