Make sky_tool much more user-friendly.
Make sky_tool much more user-friendly.

B=Fixes #187

cbracken/flutter,flutter/flutter,cbracken/flutter,aghassemi/flutter,tvolkert/flutter,cbracken/flutter,jason-simmons/flutter,flutter/flutter,cbracken/flutter,aghassemi/flutter,jason-simmons/flutter,Hixie/flutter,Hixie/flutter,flutter/flutter,tvolkert/flutter,Hixie/flutter,flutter/flutter,Hixie/flutter,flutter/flutter,tvolkert/flutter,tvolkert/flutter,cbracken/flutter,Hixie/flutter,jason-simmons/flutter,turnidge/flutter,flutter/flutter,jason-simmons/flutter,Hixie/flutter,cbracken/flutter,turnidge/flutter,cbracken/flutter,Hixie/flutter,flutter/flutter,tvolkert/flutter,flutter/flutter,tvolkert/flutter,tvolkert/flutter,flutter/flutter,tvolkert/flutter,cbracken/flutter,turnidge/flutter,Hixie/flutter,turnidge/flutter,aghassemi/flutter,Hixie/flutter,turnidge/flutter,cbracken/flutter,tvolkert/flutter,Hixie/flutter,aghassemi/flutter,tvolkert/flutter,flutter/flutter,cbracken/flutter