asFloat, asInt enhancements

A combination of a few bug fixes, additional tests, and a minor enhancement

### Enhancements
* boolean properties are now handled by asInt, asFloat. `true` maps to 1, `false` maps to 0

### Fixes
* I have removed support for null and undefined arguments to the asInt, asFloat CPMs. Exceptions are now thrown for either of these cases.
* Fixed the "setter" logic for `parseComputedPropertyMacro`. It was reusing the `parseFunction` callback inappropriately, instead of using an appropriate transformation based on dependent property type.

### Test Coverage
* Added coverage to `asInt` and `asFloat` for properties with `undefined` and `null` values
* Added coverage to `asInt` and `asFloat` for setting values, and verifying that appropriate updates to dependent properties happen
* Added coverage to `asInt` and `asFloat` for `undefined` and `null` property keys (verifies exceptions are thrown)
* Added coverage to `asInt` and `asFloat` for the aforementioned boolean value support