Moving parsing into effect components.

- Added IEffectParsable to standardize producing EffectSpan objects in
  EffectComponent objects.
- Reverted UsePowerEffect to the templated implementation. This moves
  error detection from runtime to compile time and is fewer lines of code.
Added GainBonusEffect. 5/10 criticals done.

- Renamed GrantsCombatAdvantageEffect to GrantCombatAdvantageEffect for
  consistency.
- Added GainBonusEffect and To, Until and UntilHelper classes.
- Fixed bug in Your where the wrong type was being returned.
- Added Cockroach critical effect test.

Future work:
- Add a ScoreType.TemporaryHitPoints and model it that way?
- Add a ScoreTypeHelper.ToString(ScoreType). Might already exist in the
  renderers somewhere.