Improved videosearch

This accomplishes two important things:

1) Updates video search query service to be specific to the video wiki, and allows us to specify behaviors just for video wiki search

2) Splits out searches for the video embed tool into a separate query service, using boost queries for things like category-to-hub matching and wiki title so that it doesn't pollute the initial query result set.

This pull request has been issued so that we have a clear idea of where search is this week while the team is all together. Some things left to be done that we can do after the pull request include updating the video search query service to work like other edismax query services now do, and to complete unit tests.