** Note: You may have already done this but I can't test because of #273

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
In order to do server-side filtering of the thousands of repos, we need to have a way to search by the normalized (i.e. lowercase) spelling of languages.

Describe the solution you'd like
A clear and concise description of what you want to happen.
I'd like to be able to search https://api.code.gov/repos?api_key=DEMO_KEY&languages=javascript and have it return all of the repos that are JS regardless of whether incorrect capitalization was used (e.g., Javascript, javaScript)

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.
We probably just need to add a .toLowerCase a couple times on the back-end.

Additional context
Add any other context or screenshots about the feature request here.
This is really important because the browse projects page in the redesign won't work without it.