Install fails with node-gyp errors

[glenpike]

If I try to install weak I get the following errors. I don't have Xcode installed, but I do have the command line tools. In comparison, installing node-sass is fine. See node-gyp #559 for reference - it states that shouldn't need the full Xcode.

npm install weak

> weak@1.0.1 install /Users/glenpike/test/node_modules/weak
> node-gyp rebuild

xcode-select: error: tool 'xcodebuild' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance

xcode-select: error: tool 'xcodebuild' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance