Remove standard-format. fixes #340

[mafintosh]

With this PR standard has around 250 fewer dependencies when installing.

[yoshuawuyts]

haha, lgtm ✨

[dcousens]

@mafintosh does this break standard --format?

[feross]

@dcousens Yes, it will. We're going to recommend that folks install standard-format separately from now on. The dependencies for standard-format are just too many and it makes install take way too long, even more-so with npm 3. It's not the fault of standard-format. Auto-formatting is complicated and esformatter is just a heavy dependency.

[feross]

@mafintosh This looks good, but I want to print a friendlier message to people who run standard --format in the new version. Maybe something like:

Code formatting is available in a standalone package: "standard-format". To install it, run "npm install -g standard-format".

[dcousens]

ACK 👍

[feross]

This has been merged into the v6 branch.