Don't allow voting while the thread is closed

When someone closes thread there is still option
to add vote which cause error when click on add
vote button. User shouldn't be able to add vote
while the thread is closed.

TNL-152
fix export for openassessment drafts (PLAT-249)
Make changes to the Mongo modulestore format for asset metadata.
Move the asset types under a top-level 'assets' dict to allow for
future arbitrary asset types.
Change 'basename' to 'pathname', since the attr is for storing the path.
Update translations (autogenerated message)
add disable fixme to pylintrc
Merge pull request #6161 from edx/adam/fix-openended-draft-export

fix export for openassessment drafts (PLAT-249)
Add email opt in to old login and register pages
Merge pull request #6122 from edx/clytwynec/dont-fail-diff-quality-for-todo

Clytwynec/dont fail diff quality for todo
Support unicode ANALYTICS_DASHBOARD_NAME

I open this pull to support unicode ANALYTICS_DASHBOARD_NAME
Merge pull request #5244 from mlkwaqas/waqas/tnl152-stop-voting-on-closed-thread

Don't allow voting while the thread is closed
Merge pull request #6168 from fmyzjs/patch-6

Support unicode ANALYTICS_DASHBOARD_NAME
Merge pull request #6170 from edx/will/old-login-register-email-opt-in

Add email opt in to old login and register pages
Merge pull request #6171 from edx/sarina/20141208-translation-update

Update translations (autogenerated message)
Merge pull request #6166 from edx/jeskew/modulestore_asset_md_format_changes

Make changes to the Mongo modulestore format for asset metadata.

https://openedx.atlassian.net/browse/PLAT-301