Fix to Deploying with Node 6

[mkpazon]

When running mupx with Node 6 the following error occurs:

buffer.js:106
      throw new Error(
      ^

Error: If encoding is specified then the first argument must be a string
    at new Buffer (buffer.js:106:13)
    at Readable.<anonymous> (/usr/local/lib/node_modules/mupx/node_modules/archiver/lib/util/index.js:32:15)
    at emitNone (events.js:91:20)
    at Readable.emit (events.js:185:7)
    at endReadableNT (_stream_readable.js:926:12)
    at _combinedTickCallback (internal/process/next_tick.js:74:11)
    at process._tickCallback (internal/process/next_tick.js:98:9)

This update fixes the problem.

[mkpazon]

Fix to https://github.com/arunoda/meteor-up/issues/1001 "issue mupx deploy #1001" and zodern/meteor-up#985

[MasterJames]

Oh wow is that all? ! Nicely done. I thought it was a Meteor problem and coming soon.
About a month ago I saw a YT video with the dev working on it saying 5 was working and 6 was close. (Can't find it now)
At least to be bundled with meteor. Maybe this is just a change for mupx to work?
Anyway only the new version is accepting PRs kadirahq/meteor-up so maybe see if this helps there too.
Again great find thanks.

[CarlQLange]

Can this please be merged?