Added documentation to new acceptance test features and techniques
vagrant: Always mount `node_modules` folder after Vagrant NFS mount
Add a 'string literal' serialization method and use it in the lambda function mapping table when the value to xml serialize is of basestring type. Also a couple of drive-by pep8 fixes.
add new tests for the string literal serialization
fix up some of the test courses which had hardcoded that quot; escaping
use better syntax for asserting that exception is thrown
raise a more appropriate Exception
Merge pull request #383 from edx/jonahstanley/add-test-documentation

Added documentation to new acceptance test features and techniques
Merge pull request #384 from antoviaque/vagrant-mount

vagrant: Always mount `node_modules` folder after Vagrant NFS mount
change serialize_field to check for type. If value is a string, simply return that, otherwise do a json.dumps
Merge pull request #387 from edx/fix/cdodge/unescape-quote-strings

[STUD-406] Fix/cdodge/unescape quote strings
Merge branch 'master' of github.com:edx/edx-platform into feature/kluo/bulk-email
Add tests for exception handling in bulk email task functions