function getSymlinks (cwd, pkgJson) {
	const libSymlink = [cwd, path.join(config.globalNodeModules, pkgJson.name)]
	let bin = pkgJson.bin
	if (typeof bin === 'string') {
		bin = {}
		bin[pkgJson.name] = pkgJson.bin
	}
	bin = bin || {}
	const binSymlinks = Object.keys(bin).map((name) => ([
		path.join(config.globalNodeModules, pkgJson.name, bin[name]),
		path.join(config.globalBin, name)
	]))
	return [libSymlink].concat(binSymlinks)
}
generate the symlinks to be created in order to link to passed in package.
@param {String} cwd - current working directory.
@param {Object} pkgJson - `package.json` file to be linked.
@return {Array.<String>} - an array of tuples representing symbolic links to be
created.