Document policy about when we do QA testing

TESTING_AND_QA.md

+# QA Policy
+
+As [documented in this conversation with
+LFC](https://chat.opentechstrategies.com/#narrow/stream/45-Lever-for-Change/topic/100.26Change.202025/near/196737),
+we perform a regular monthly QA, plus an additional QA round before
+any wide release to a donor.
+
+This policy applies to Lever For Change.  Anyone else deploying Torque
+can have whatever QA policy they want, of course.  If there are
+multiple deployments, then we can move this policy statement to a more
+LFC-specific location.  For now, it's here for convenience.
+
 #  Basic Torque Functionality
 
 ## Basic Login