Fix compilation errors with red_hash and red_test
Rename zjson.h to red_json.h and update contents accordingly
Rename zjson.c -> red_json.c and update contents appropriately
Move red_json out of under_construction

It's not quite ready for prime time yet, but it needs to be soon, so lets do
the development here.
Fix compilation warning in red_bloom.c
Add simple makefile for building libred.so
Add libred.so to .gitignore
Fix many compilation errors with red_json
Rename zstring -> red_string and move out of under_construction
Fix compilation errors with red_json and red_string