Issue 499: support MySQL "UNIQUE KEY (ID) USING BTREE" constraint syntax


git-svn-id: http://h2database.googlecode.com/svn/trunk@4963 e6896862-9d19-0410-bfb3-e9fa5d50e656
Fix build

git-svn-id: http://h2database.googlecode.com/svn/trunk@4964 e6896862-9d19-0410-bfb3-e9fa5d50e656