docs(CHANGELOG): add v1.3.0-beta.15 and v1.2.20 changes
docs($parse:isecdom): add a section about return values and CoffeeScript

Closes #7973
docs($http): remove invalid JSDOC tags for patch() method

The @methodOf tag was causing a warning on build. I removed the tag and changed the @name to match
the previous comment blocks.

Closes #8170