Open nitpicking on submission, not completion. Fixes #714.
Fetch correct exercises from API
haskell palindrome-products
haskell pascals-triangle
Merge pull request #720 from etrepum/haskell-examples

haskell exercises
Add missing nitpick lists. Fixes #723
haskell pig-latin
Merge pull request #724 from etrepum/haskell-examples

haskell pig-latin
Add alternate Bob example in Elixir
Don't set next exercise on completion.

Whatever they submit when they don't have a current exercise for a
language will become the current exercise.
No longer need to activate a language before submitting
Delete left-over email code
Get rid of concept 'approval'
Merge pull request #728 from shepmaster/no-need-to-activate

No longer need to activate a language before submitting
Change status of latest submission to 'done'

Sometimes people click "I'm done" on an earlier iteration of an
exercise. In these cases, the earlier (superseded) submission was being
set to 'done' whereas the 'pending' one was left pending.
Remove hoaky 'congrats' placeholder
Replace thymine w/ thymidine for consistency & accuracy [Fixes #725]
Don't leave current assignment lying around
Clarify which exercise gets unlocked. Fixes #658
Change expected implementation file name for consistency