add ArraySugar annotation for auto magic chains

this lets categories set a handler for 'unexpected' array types
over their base type. ie. instead of 'thing: {type: a, field: 5}',
you may arbitrarily put in 'thing: [{type: a, field: 5}, ...]' as
long as your base type has a chain-like implementation is is
annotated correctly.
Merge pull request #5 from addthis/array-sugar

add ArraySugar annotation for auto magic chains