Merge pull request #56 from OpenPhilology/development

API changes (smyth -> ref), Frontend cleanup, tasks.
Enable empty word cts.
Updated smyth to ref in identify_letter and base task.
Merge branch 'master' into development
Linux time conformity.
Merge branch 'master' into development
Get the user better.
Merge branch 'master' into development
Caught key error.
Merge branch 'master' into development
Make "ref" field on Grammar Topic read-only on edit.

This is because the endpoints that provide us user information about progress, accuracy, etc. are coupled to this data.
So if someone, not knowing, were to change this value, they would basically screw up user data.