`transformer resolve` should install

[jbenet]

Right now:

> transformer install unix-time js-date iso-date
Installed:
- transformer.unix-time
- transformer.unix-time-to-js-date
- transformer.js-date
- transformer.js-date-to-iso-date
- transformer.iso-date

Future:

> transformer install unix-time js-date iso-date
Installed:
- transformer.unix-time
- transformer.js-date
- transformer.iso-date

> transformer resolve --install unix-time js-date iso-date
Installed:
- transformer.unix-time
- transformer.unix-time-to-js-date
- transformer.js-date
- transformer.js-date-to-iso-date
- transformer.iso-date

Notes:

• transformer install a b c should only install a, b, c not a, a2b, b, b2c, c. that should include an explicit resolve step.
• atm there is a double resolve step, one for types, one for conversions. this will go away when resolve is smarter.