Build failure due to spaces in path #180

When installing a native module using node-gyp, commands fail to run if there is a space in the path anywhere of the CWD.

A CWD like /home/abc/My Awesome Repo/project will fail.

This has been discussed here: kelektiv/node.bcrypt.js#961
and here: nodejs/node-gyp#65

And has been found to be an underlying issue with gyp itself