Move comment checks into their own module

hacking.core is getting too big, this is the first patch to pull out a
group of checks (H1xx) into their own module.

Change-Id: Ibd0668be59ce6a440b94788692d3784da24d70d8
Move except checks into their own module

Move except (H20x) checks into their own module. The module cannot be
called just 'except' since that is a reserved word.

Change-Id: I22259e9af4d8b1b87012007c5c5f599f8533013c