Only use buttons for submissions with reviews or comments

The rationale being that some people iteratively send in their
exercises, without awaiting comments. This makes it really hard to
judge if you're looking at submission 8 whether a whole discussion has
already been had, or whether no discussion has been had at all.
Meetup exercise for Common Lisp.
Improved styling

created proper style for deemphasized button,
also fixed styling of active submission
Move some tests around

Testing allergic_to? make a bit more logical sense because it will be used
later to implement .list.

Also removed a couple of tests that were duplicative.
Use refute

This makes it a bit more semantic and exposes people to both assert and refute
Fix timezone bug in nitstats
Add a little Unicode to bob

The idea is to make people aware that `[A-Z]` is not a good regex for checking
for letters.
Simplified the instructions for submitter/nitpicker

There are a lot of directions to the right of the submission, especially on the first submission. I tried to make this a bit cleaner.
Do not hibernate submissions where submitter is last commenter
Specify minitest gem in test helper
go/accumulate: changed 'Allergies' to 'Accumulate', added tests
Use the right order of args in elixir list-ops reduce

The function passed to reduce should take args `element, acc`, not `acc,
element` to be consistent with `Enum.reduce`.
Fix in nit_count update when submitter == user

The nit_count shouldn't be updated when deleting a submitter's comment.
Changed grade school to eliminate db reader

Changed everything to only consider the sorted way of accessing the database. Called this access to_hash.

Fixes #1275
update assignments from rust-0.8 to rust-0.9
Adding lisp grains exercise.
List hibernating exercises in account
Expose test suite. See #1135
Clarify hibernation on submission
Removed code which uses stash functionality