Initial JsonReader impl.
Lightened burden on JsonReaders and moved a lot of stuff in the playground package.
More movement.
Leaned up the JsonReaders

ArrayReader is now ArrayIterator, an iterator type object. Fits the
access pattern better I believe. Simple is good here.
Got simple deserialization working again

Also fixed some path dependent stuff.
Kind of have list working

Doesn't work with anything but list though.
Mostly working again, need Maps

Got most of the Deserializer working again, not counting maps.
A little cleanup and made the benchmarks work again.
Big cleanup

Also removed unneeded exception and added more unit tests.
more cleanup

Brought naming inline to be more consistent throughout the deserializer.
initial text reader

Object side is working. Parser is really sloppy.
Added TextArrayIterator

The functionality is complete. Needs a lot more testing. Need helper
methods to directly stuff json into that will choose array vs object and
make a reader.
cleanup of text reader

There is a corner case on strings that needs taking care of.
Made initial deserialization simpler

Get right reader and send it to macro using the Macros.read[U](str)
method.
Fixed corner case
Moved to linear parsing

Got a small performance boost too.
Generalized TextCursor

Now it may be useful for other serialized structures as well.
Merged text cursor parts.
Abstraction doesn't seem worth the performance loss. May reconsider if I decide to write a parser for another serialization structure.
Cleanup of the JsonReader default impls.
Make them throw a reasonable error instead of a None.get on missing field.