Added a windows-specific `tee` equivalent#561

Merged

Michael-F-Bryan merged 3 commits intorust-lang:masterfrom

Michael-F-Bryan:windows-tee

Jan 20, 2018

Commits on Jan 19, 2018

Added a windows-specific `tee` equivalent
Michael-F-Bryan
committed

Commits on Jan 20, 2018

Changed how the windows "tee" command gets quoted
Michael-F-Bryan
committed
Temporarily disabled the backends_receive_render_context_via_stdin test
Michael-F-Bryan
committed