[bugfix] Moved `INSPECT_MAX_BYTES` to the buffer module.

From the [docs](http://nodejs.org/api/buffer.html#buffer_buffer_inspect_max_bytes):

"Note that this is a property on the buffer module returned by `require('buffer')`, not on the Buffer global, or a buffer instance."
Merge pull request #2155 from johnnycrab/master

node.js: [bugfix] Moved `INSPECT_MAX_BYTES` to the buffer module.