OverconstrainedError == ConstraintNotSatisfiedError?

As far as I can tell, the only difference between 
ConstraintNotSatisfiedError and OverconstrainedError is when they happen.

The former only happens in getUserMedia, while the latter only in the 
overconstrained event. The latter seems to me like the runtime 
equivalent of the former, so in the interest of reducing the 
proliferation of errors I propose we remove the OverconstrainedError 
name and use ConstraintNotSatisfiedError in both places.

.: Jan-Ivar :.