Update to Introduction to QA webpage

[Rob Weir <ro...@apache.org>]

I've updated the Introduction to QA page based on the common questions
that have come up since we introduced this page late last year.  I
recommend that new volunteers take another read, especially in the
section called "Easy QA Task: Confirm New Defect Reports" since I've
added more material there which should make the process clearer.

http://openoffice.apache.org/orientation/intro-qa.html

Thanks!

-Rob