Add ability to specify stream URL

[shusugmt]

Solves #143

• st2client.js needs to be updated since 0.4.3 does not support specifying stream url
• Use utils.parseUrl() just like ST2_AUTH_URL do, even the same logic is implemented in st2client.js (here and here)
  • We can just pass single string to opts.auth or opts.stream and let st2client.js handle URL parsing, but that is out of the scope here. If we want to do that, we should do it in separate PR.

[LindsayHill]

@armab I think that dropping nodejs 0.12 tests makes sense. (https://github.com/StackStorm/hubot-stackstorm/pull/144/commits/d6092198162bc008b059adb5a3fa33b69296a64c). What do you think?

[Kami]

Change looks good to me :+1:

/cc @armab

[shusugmt]

@armab Thanks for review.

CHANGELOG update mentioning:

• dropping node.js 0.12 support
• updating st2client to 1.1.1
• adding ST2_STREAM_URL

I thought this should be done in release commit? like:

• https://github.com/StackStorm/hubot-stackstorm/commit/af65d339e08aa6d7959a0c5fa3720ebe705dc188
• https://github.com/StackStorm/hubot-stackstorm/commit/751f2bec4dceb53e2e16c536feb7e26a77d70359

[arm4b]

The previous changes went into Changelog in one commit because there was nothing else to add (1 change = 1 release). In case of more changes, - it's preferred to include what was done in the changelog as part of PR. Would be easy for release manager so he don't need to grab the git history.

This is similar to what we do in StackStorm/st2, ex: https://github.com/StackStorm/st2/pull/3849/files

[shusugmt]

@armab changelog updated!

[arm4b]

Merged, Thanks!