Solve day sixteen

Add day 14 description

Solve day fourteen

rustfmt

Rewrite day 13 for SPEED!!!

Add descriptions for days 11 to 13

Solve day thirteen

Minor optimization

Don't grow line if we don't have to.

Make heuristic bound smaller

Solve day twelve

Solve day eleven

Optimize, minor tweaks

Small edit

rustfmt, day 9 description

Solve day 10

Solve day nine

rustfmt

Reduce allocations, don't actually build tree

Solve day eight

Replace HashMap with FxHashMap

cleanup