[CLI] Options parsing, add support for --version

[pedro]

• Using commander to parse command line options so it's a bit more declarative/extensible
• Support for react-native --version

[vjeux]

Looks good to me, @frantic what do you think?

[gaearon]

Commander wasn't a nice option for Babel:

babel/babel#836 (comment)
babel/babel#756 (comment)

[frantic]

@pedro why commander? Did you consider any alternatives?

[pedro]

Interesting – I just went with Commander because of the nice interface and how it wraps stuff like the help view. Looked at minimist too, but it's pretty raw so we'd still have to do validation/help screen/etc.

And just found argparse, thoughts on it?

[brentvatne]

ping @frantic

[frantic]

We already use optimist in RN, can we use it for this as well for consistency?

[pedro]

For sure, sounds good! I'll bring it in in another pull.
Thanks folks!

[frantic]

🆒 Also note there is #1125 that is likely to be merged in