+quote.
KVC protocol.
KVC combinator.
-quote.
Alternation quoting.

Right syntax, wrong semantics—this won’t work until the semantics of
`-and:` are corrected. cf #96.
Merge branch 'master' into quote

Conflicts:
	Hammer.xcodeproj/project.pbxproj
	Hammer/HMRAlternation.m
	Hammer/HMRCombinator.m
KVC combinators have descriptions.
KVC combinators are predicates.
Kind-of combinators have better descriptions.
Terminal combinators are quoted as literals.
Delay combinators pass KVC on.
Intersections always compact validly.
Already compacted intersections compact to self.
εx ∩ εy ⇒ ε{x ∩ y}

The intersection of null parses compacts to the null parse of their
intersection.
εx ∪ εy ⇒ ε{x ∪ y}

Generalize the compaction of the union of identical null parses to the
union of any null parses.
Alternation quoting applies KVC.
Removes the cyclicity operation.

Not sure how this got missed.
Obsolete alternation predicate.
Intersection quoting.
Obsolete intersection predicate.