Allow filtering current by language
Merge pull request #63 from Tonkpils/filter-current

Allow filtering current by language
Bump version
Run go fmt
Mark exercises as new. Fixes #66

When fetching new exercises, it's helpful to have an indicator of which
exercise you have not yet submitted any code for, especially since the
exercises are now listed in alphabetical order, not in any particular
order of completion.
Bump version