docs: Add instructions for using qtcreator's issues pane

Add instructions for getting compiler errors into qtcreators Issues pane
when building with ninja, and other general cleanup.

TBR=chaopeng@chromium.org

Change-Id: I23e238e48a688a993cf2b40b9979f94d9fe18305
Reviewed-on: https://chromium-review.googlesource.com/680715
Reviewed-by: Sam McNally <sammc@chromium.org>
Reviewed-by: Chris Watkins <watk@chromium.org>
Commit-Queue: Chris Watkins <watk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#504543}
1 file changed