node-gyp@0.8.1

Add backfill feature
Updated code to be fully async, consistent indentation
Merge branch 'backfill' of github.com:lloydwatkin/npm into backfill
Skip over non-package things
Use npm.prefix not '.'
Use resolve properly
2-space indent
Death to semi-colons... ';'-pocalypse
'async'-out --> 'slide'-in
Add ~ in front of package version numbers like --save
Removed async dependency
Add '~' in front of version numbers
Write to appropriate package key
Apply updates to different dependency key like with --save
If key doesn't exist create it, handle bundle dependencies slightly differently
Removed trailing whitespace
Update docs to match