Changes to obtain deterministric results in transcript tests.

I discovered late that gremlin with tinkergraph does not guarantee deterministic
ordering of results, making the transcript tests unrepeatable. I had done most
of my testing on my MacBook, which seems to deliver repeatable results. But
Travis tests on Linux, which gives results with different ordering. I am somewhat
puzzled by this, because I had used Travis for many successful test runs before
this problem materialized. It seems to be related to my use of Q promises
in gremlin-node, but I haven't yet figured out the true root cause.
And nvm 0.11 back to test matrix, and test with latest json-stable-stringify.
Use master branch from jlloyd/json-stable-stringify.git instead of feature branch.
Remove references to package object-inspect.
Merge pull request #14 from jimlloyd/feature/fix-for-unstable-sort.2

Fix for unstable sort