Fix a typo in README
Ordering dts to order more important concepts towards the top
Clarify some aliases
Expose __empty, __make on prototype

Adds makeEmpty helper for generic construction of empty values.
Provides __emptyMap, __emptyList, __emptyOrderedMap for changing
base types of OrderedMap, OrderedSet, etc.

Still need to take a look at how updateInDeepMap works with
custom type behind OrderedMap
Should preserve types in updateInDeepMap