perf($q): move Deferred and Promise methods to prototypes

Opening PR for tests and comparison with other solutions for `$q` perf.

NOTE: Deferred doesn't get all the advantages of moving methods to the prototype,
since the constructor binds instance methods to "this" to support unbounded execution.

NOTE: This change increases the gzipped version by 100 bytes.
we can likely get slightly better perf in v8 (at least) by not using native Function.bind, but instead just implementing a simpler bind1() which doesn't worry about all of the corner cases. I don't care that much about this though.