Signame in JSON is optional; just default to unnamed
Use globals() instead of eval()
Add back first set of tests; use CephInt instead of IntType
Allow validate_one to raise exception
Fix 'N'; continue grabbing even when numseen == n; fix test instead
Accumulate JSON in validate, return it
CephInt instead of int/IntType
Give fields names so that JSON is sensible
bit_length doesn't work rationally for negative ints.  Drop it.
default 'name' to 'cmd'
Add sig, blank line to try_validate
wip