DERBY-6667: Make Test_6661 create its own, empty, single-use database; commit derby-6676-01-aa-singleUseDecorator.diff.

git-svn-id: https://svn.apache.org/repos/asf/db/derby/code/trunk@1614077 13f79535-47bb-0310-9956-ffa450edef68
DERBY-6665 Violation of deferred constraints not detected when conglomerates are shared

Patch (derby-6665-dhw-dont-share) to fix missing logic to exclude
deferrable foreign key constrants form sharing supporting index. Adds
repro tests to ForeignKeysDeferrableTest.

git-svn-id: https://svn.apache.org/repos/asf/db/derby/code/trunk@1614327 13f79535-47bb-0310-9956-ffa450edef68