Auto merge of #2421 - sbeckeriv:decolor-messages-426, r=alexcrichton

Dull the errors

This resolves #426

Dearest Reviewer,

I have updated the error messages to use say_status at the shell level. I have also changed say_status to print the message in bold. I do think it looks nice but it does have the side effect of making some seemingly unrelated text bold. I do think it looks better bold but it is also very easy to revert. I have included examples of both.

Thank you,
Becker

Bold: Note the usage is bold.
<img width="1072" alt="screen shot 2016-02-27 at 10 49 05 am" src="https://cloud.githubusercontent.com/assets/12170/13374778/0efd54ec-dd43-11e5-9f02-f0224608132a.png">

No bold:
<img width="885" alt="screen shot 2016-02-27 at 10 46 35 am" src="https://cloud.githubusercontent.com/assets/12170/13374775/fa3a6612-dd42-11e5-9c09-8f23506f5f0c.png">

Both rendered on a mac with iterm 2.9.0