replace `console.log` with `console.error`
replace `console.log` with `console.error`

Summary:
@public

Tools using stdout to communicate machine-readable information to other processes are easily broken by using `console.log` (which prints to stdout). Switching to `console.error` will print to stderr instead, and not interfere with ipc.

Reviewed By: wez

Differential Revision: D4461585

fbshipit-source-id: 2b550b4ca5d26a36f7bf0c7181d924a7140a89af

facebook/watchman,kwlzn/watchman,nodakai/watchman,facebook/watchman,nodakai/watchman,kwlzn/watchman,facebook/watchman,wez/watchman,facebook/watchman,kwlzn/watchman,kwlzn/watchman,wez/watchman,facebook/watchman,kwlzn/watchman,kwlzn/watchman,facebook/watchman,wez/watchman,nodakai/watchman,nodakai/watchman,nodakai/watchman,facebook/watchman,nodakai/watchman,facebook/watchman,wez/watchman,nodakai/watchman,facebook/watchman,wez/watchman,kwlzn/watchman,wez/watchman,nodakai/watchman,wez/watchman,wez/watchman,wez/watchman,nodakai/watchman