adds a couple missing anagram tests

- anagrams must not be the source word case-insensitively
- anagrams must use all letters exactly once

Without these tests, it was possible for match functions to pass all
tests while still not being entirely correct.
Merge pull request #654 from jeremy-w/elixir-anagram-missing-tests

adds a couple missing anagram tests
haskell octal
 haskell trinary
haskell wordy
Fix flash on exercise completion. Fixes #658.
Merge pull request #656 from etrepum/haskell-exercises

haskell octal
Do not transfer likes to the next submission
Introduce `liked` fields on Submission

As a first step, duplicate the existing `approvable` fields, and write
to both places. This will allow us to migrate existing data, then switch
over to use the new fields while deleting the old ones.
Use liked rather than approvable
State who liked the assignment. See #657.
Show liked checkmark on dashboard. See #657.
Don't ask for more opinions on completed exercises
Make `looks great` its own thing.

Don't tie it together with nitpicks. Move it out of the nitpick form,
and put it closer to the code so it's less likely that one would click
it by accident.
Delete unused code
Don't notify on complete (seed data)
Add notification for likes. See #657
Move the looks great button