Add link in lms legacy instructor dashboard to cms course_index

A one-click way of getting to editing the course
Pass in harvest args to fasttest_acceptance, not the args array
add nltk to sandbox reqs
Merge pull request #861 from edx/fix/adam/add-edge-reqs

add requests and nltk to sandbox reqs
add nltk to sandbox reqs
fix simple things because, damn
Don't fetch the editor for XML courses
Merge pull request #863 from edx/ned/fix-simple-things-because,-damn

fix simple things because, damn
Address review comments for lms_link_to_cms

* Uses override_settings to provide test variable
* Move location of cms link to upper right
* PEP8 / Pylink
Merge pull request #859 from edx/jbau/studio-link-in-instructor-panel

Add link in lms legacy instructor dashboard to cms course_index
Fix selector.
Fix test.
Merge pull request #868 from edx/hotfix/lose_header_bug

Fix bug when editing video causes other components to lose their header
Fix selector.
Fix test.
vagrant: Add flag to ensure install is completed at least once

The provisioning script used to check for the existence of the
`/opt/edx/node_modules` folder to decide if the installation has already
been completed. However, since additional instructions were executed
by the installer afterwards, any installation error (eg. download
timeouts on low quality connections) happening between the creation of
that folder and the end of the installation wouldn't be recovered from
on the next vagrant instance boot.
due to the MixedModuleStore pending release, we need to make enrollment start/end dates editable in Studio
Merge pull request #871 from edx/fix/cdodge/re-enable-enrollment-start-stop

due to the MixedModuleStore pending release, we need to make enrollment ...
Don't show course about page link when we have the marketing site.

STUD-733
Merge pull request #634 from antoviaque/vagrant-provisioning-resume

vagrant: Add flag to ensure install is completed at least once