R1:dfa9b27a949c

Use tabs on build targets and allow build steps to have a description

Summary:
Ref T1049. This uses tabs on build targets to hide the configuration details and variables by default, instead promoting the target name, it's status and a description of the build step. The description is a new field on each build step.

The primary advantage of having a description on build steps is that DevOps can configure appropriate description information (including any troubleshooting information for build failures) on…