chore(npm): bump chokidar and test against node@^6.0 (fixes #824)

[mgcrea]

No description provided.

[mgcrea]

nodemon fork should start a fork exec with a space with args (escaped) is failing but does not seem related to the chokidar issue. Any ideas?

[remy]

I've kicked the test.

[remy]

Merged manually so that the change included a fix commit (that triggers a bump of version).

Thanks so much for this!