gh696: fix project filter for tasks

Replaced old code to reset the filter with one that simply searches
the DOM for the option that was originally selected and selects that.

Also improved the template a bit:
* Made the any project have the selected attribute if project=None
* Made the HTML for the options not span multiple lines
gh757: make back button reset project filter for team videos page

There is more to this bug, but I think my last commit may have caused
a regression here, so I want to fix this part before merging.
Merge pull request #763 from pculture/gh-696

Gh 696