package.json: Bump version to v4.5.0
package.json: Remove gitHead, per npm/npm#3363
package.json: Update devDependencies

Apparently node automatically defaults to 2-space indentation for
package.json, so I'll just leave that there.
package.json: Use https Git URL
package.json: Add description
package.json: Add homepage and fix license name
package.json: Mark project as private
Merge pull request #1480 from mc10/package

Adjust package.json