Use jsxc instead of commoner

Noticed several bug reports in the past few days on IRC. Still think commoner is the wrong tool for this job and jsxc is the right one.

Test plan: tested jsxc using the normal test plan. Ran bin/jsx, behaved same as jsxc
optimist is actually dead. Maybe we should use [yargs](https://www.npmjs.org/package/yargs) (successor to optimist), [commander](https://www.npmjs.org/package/commander) (probably the most popular argv parser), or [nomnom](https://www.npmjs.org/package/nomnom) (one of my faves).