[API] Label Limitations

Hey there guys

Working on the Android app. Right now, there are a lot of limitations with the Labels API.

1. When I retrieve issues for a project, the label array is just the list of label names, without the colors, which I would love to be able to display the colors too. Why not make it an array of label objects?
2. When I retrieve all labels for a project (/projects/{id}/labels) I need to know how many open issues fall under each label in order to create similar UI to what you see on the web.

Thanks for all the hard work!