%g: NotImplementedError

[alanjds]

Spawning from google#305 (comment) %g formatting is not yet implemented:

(grumpy) kirr@deco:~/src/tools/go/grumpy$ cat g.py 
#!/usr/bin/env python

print '%g' % 1.0
(grumpy) kirr@deco:~/src/tools/go/grumpy$ python2 g.py 
1

(grumpy) kirr@deco:~/src/tools/go/grumpy$ grumprun <g.py 
NotImplementedError: conversion type not yet supported: g
exit status 1