isValid should not trigger an exception if the connection is closed.

git-svn-id: http://svn.apache.org/repos/asf/commons/proper/dbcp@1568965 13f79535-47bb-0310-9956-ffa450edef68
Fix DBCP-357. Use Connection.isValid() to validate connections unless a validation query has been defined.

git-svn-id: http://svn.apache.org/repos/asf/commons/proper/dbcp@1568981 13f79535-47bb-0310-9956-ffa450edef68
Complete rename of maxActive to maxTotal

git-svn-id: http://svn.apache.org/repos/asf/commons/proper/dbcp@1568985 13f79535-47bb-0310-9956-ffa450edef68
Functionality this was testing has been removed.

git-svn-id: http://svn.apache.org/repos/asf/commons/proper/dbcp@1569096 13f79535-47bb-0310-9956-ffa450edef68
Now validation is using isValid() it needs a basic implementation here.

git-svn-id: http://svn.apache.org/repos/asf/commons/proper/dbcp@1569097 13f79535-47bb-0310-9956-ffa450edef68