Added compilation support for Node.js v4

[braydonf]

Closes: bitpay/bitcore#1361
Closes: #259

[kleetus]

is there a stray space here? I can't tell exactly.

[braydonf]

I'll remove it, there is a space there.

[kleetus]

this worked ok on debian jesse, but on Mac 10.10, it get:

module.js:339
throw err;
^

Error: Cannot find module 'db/package.json'
at Function.Module._resolveFilename (module.js:337:15)
at Function.Module._load (module.js:287:25)
at Module.require (module.js:366:17)
at require (module.js:385:17)
at Function.setupServices (/Users/chrisk/source/zzbitcore_node/lib/scaffold/start.js:51:30)
at start (/Users/chrisk/source/zzbitcore_node/lib/scaffold/start.js:203:31)
at Object. (/Users/chrisk/source/zzbitcore_node/bin/start.js:8:1)
at Module._compile (module.js:435:26)
at Object.Module._extensions..js (module.js:442:10)
at Module.load (module.js:356:32)

when running:

node bin/start

node 4.2.1

[braydonf]

I don't think bin/start is supported anymore.
Edit: Working here, that issue may not be related.

[kleetus]

works using ./bin/bitcore start and removing insight related plugins from bitcore-node.json

[kleetus]

LGTM

[pnagurny]

tested - works locally. LGTM