Added Coercion

Changes:
-json and schema can be a parsed object as well as a json string
-Added coerce property to Validator object, triggering coercion mode
-Coerce rules:
	* Array:
		--no default sends errors like before
		--when not an array, sets element value to default
		--items < minimum, sets element value to default
		--items > maximum, truncates to maximum items
		--when not unique, removes non-unique values
	* Boolean:
		--no default sends errors like before
		--when not a boolean, sets element value to default
	* Integer:
		--no default sends errors like before
		--when not an integer, sets element value to default
		--items < minimum, sets element value to default
		--items > maximum, sets element value to default
		--when not in enum, sets element value to default
	* Null:
		--no default sends errors like before
		--when not null, sets element value to null
	* Number:
		--no defaults sends errors like before
		--when not a number, sets element value to default
		--items < minimum, sets element value to default
		--items > maximum, sets element value to default
		--when not in enum, sets element value to default
	* Object:
		--no defaults sends errors like before
		--when not an object, sets element value to default
	* String:
		--no default sends errors like before
		--when not a string, sets element value to default
		--length < minimum, sets element value to default
		--length > maximum, truncates value to maximum
		--when not in enum, sets element value to default
	* Union
		--no changes