Auto merge of #438 - UK992:buildbot-steps, r=aneeshusa
Auto merge of #438 - UK992:buildbot-steps, r=aneeshusa

Add description to buildbot steps

Fixes https://github.com/servo/saltfs/issues/337

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servo/saltfs,UK992/saltfs,rwaweber/saltfs,UK992/saltfs,UK992/saltfs,rwaweber/saltfs,ALikhachev/saltfs,ALikhachev/saltfs,rwaweber/saltfs,servo/saltfs,ALikhachev/saltfs