Pulled out mvndst parameters

********* PEOPLE *************
Primary reviewer: @sc932 

Reviewers: @suntzu86 

********* DESCRIPTION **************
Branch Name: denizokt_376_fixflakes
Ticket(s)/Issue(s): Closes #376 

********* TESTING DONE *************
make test
make style-test
made sure demos and pretty endpoints still work
restructured text stuff:
you want:
```
... consult: http://...

.. Note:: blah blah blah
  at least 2 space indent for the line continuation
```
to make a nice colorful "note" block and also prevent the "NOTE" block from being combined w/the previous line