select: select option if there is only 1 option

[jobo26]

Feature request: automatically select option from md-select if there is just 1 option.
Maybe this could be an optional setting on the directive.

Actual Behavior:

• What is the issue? *
  I want to improve the usability of my form by pre-selecting values from md-select items if they only have 1 option.
• What is the expected behavior?

CodePen (or steps to reproduce the issue): *

• CodePen Demo which shows your issue:
  http://codepen.io/joranbodt/pen/dpXNoE
• Details:

Angular Versions: *

• Angular Version:
• Angular Material Version:

Additional Information:

• Browser Type: *
• Browser Version: *
• OS: *
• Stack Traces: