Upgrade gwtorm to 1.11

This version of gwtorm contains an important bug-fix that ensures that
"LIMIT ?" is not omitted in generated queries [1]. This can improve the
performance of such queries by a large factor.

[1] https://gerrit-review.googlesource.com/57216

Change-Id: Ibd0d3918629b2901288de6dd2e85489e4503091a
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
Merge "Upgrade gwtorm to 1.11" into stable-2.9