Hashap key generic interfaces

[chuckyvt]

This is update to the hashmap capabilities to include generic key interfaces for most of the type-bound procedures that use key type. I believe this will be a nice step forward for the user interface, reducing number of lines of code to use the hashamaps, and makes it closer to the style of a dictionary in Python.

For example, currently to map an entry:

call set( key, [1] )
call map % map_entry( key, other, conflict )

This simplifies to call map % map_entry( [1], other, conflict )

This is the initial submit with src and testing updated for review. Will work on specs and adding examples next.