Edited the doc to have more detailed and helpful instructions for the mac installation
Revert "Edited the doc to have more detailed and helpful instructions for the mac installation"

This reverts commit f35d140383538718fb295ff3b222d226848152f2.
Merge branch 'master' of https://github.com/Stanford-Online/class2go
readme changes
added date & time to navbar as per request
fixed display issues on phones and small tablets
edited readme to make virtual env wrapper optional
commented out time in header until we figure out where we want it
Merge pull request #2040 from Stanford-Online/giulio-working-2

Fixed some display issues (class css bg, small tablet layout, and phone class bg image and padding)