add action to lesson
starting to add likes.
first commit for feature. wrote code, didn't run it yet.
Merge branch 'develop' into feature/LERGO-281_add_like_to_lesson
finished implementation for like. - now need to add
 - show like
 - unlike
 - show likes count
LERGO-281, LERGO-301 - finished implementing like mechanism for lesson.
Merge pull request #18 from lergo/feature/LERGO-281_add_like_to_lesson

Feature/lergo 281 add like to lesson