Added doc, benchmark and deps/X node core PR labels

[phillipj]

This improves the current node core auto PR labelling functionality by supporting these extra labels:

• doc for exclusive doc/* changes
• benchmark for exclusive benchmark/* changes
• v8, libuv, openssl etc when having changes in deps/X/*

Also ignores changes to src/node_version.h to avoid labelling that as c++ as mentioned in #31 (comment).

@jbergstroem @mscdex @Fishrock123 does these labels sound reasonable to you?

Refs #31, nodejs/node#6247

[phillipj]

I'm merging this as no objections has been raised.

[williamkapke]

post LGTM! ;)

[phillipj]

@williamkapke thanks! 😄

[Fishrock123]

belated LGTM. I'll try to find time to tackle some of the more complex ones soon

[Fishrock123]

nodejs/node#6432 Seems to have been labeled as test when it doesn't only contain tests. Investigating.

[Fishrock123]

Hmm, seems like this doesn't only label test, doc, benchmark if it only contains those files, but rather if it is only one of those labels. I'll try to fix tomorrow.

[phillipj]

Hmm, seems like this doesn't only label test, doc, benchmark if it only contains those files, but rather if it is only one of those labels. I'll try to fix tomorrow.

Woops, cause the old isOnly() got removed and we're obviously missing a test for that behavior.

@Fishrock123 goodie! I'll be ready to deploy as soon as you've got a fix ready.