file_to_nsq: a utility for STDIN or file to NSQ

[elubow]

There are utilities that pull data from NSQ and write it to disk or nsq_to_http, but there is not a utility to take a file or an input stream and pipe it into NSQ. This should be added and probably work similarly to grep where it can either work on a file or work from STDIN.

[davemarchevsky]

We've been using https://github.com/bitly/file2http for this purpose, you might be able to repurpose some of that code.

[mreiferson]

there's also this: https://github.com/datastream/nsqtools/blob/master/file_to_nsq/main.go but needs a bit of refactoring

[mreiferson]

closed via #416