Add JSON parser library.

Code is v1.0.0 unmodified from [1] distributed under BSD 2-Clause license.
Code changes are hosted at [2].

[1] https://github.com/udp/json-parser
[2] https://github.com/cooperative-computing-lab/json-parser
Add sqlite3 v3.8.2 amalgamated library
Add helper library for dealing with file descriptors.
Add Chirp Job interface.
Cleanup Chirp children.
alphabetize/organize makeflow headers
Chirp batch job module and some reengineering.

This commit reengineers batch job to better support modules.  A bare-minimum
file system layer is added to allow files to be off the local file system.
Correct wrong format qualifiers.
Conditionally include Linux-specific sched.h code.