Clean copy-pasted unused headers
Make a perf printing function and put it in common code, modify all tests to use it.

Some other trivial cleanups also snuck in.
Remove unused -C option from getopt
Rename get_elapsed_ms -> get_elapsed, make it more general and port over other tests.
Add yaml header for multiple document parsing
Merge pull request #52 from pmmccorm/master

Common code + cleanups for fabtests