MdsalLowlevelPy library using True instead of true

with the Aluminium MRI bump it seems that we can no longer use True for
a boolean in the mdsallowlevel library tooling. It probably just needs to be
changed to true (lower case).

example:
https://logs.opendaylight.org/releng/vex-yul-odl-jenkins-1/controller-csit-3node-clustering-tell-all-aluminium/97/robot-plugin/log.html.gz#s1-s2-t7-k7

need to validate these things in Aluminium as well as Magnesium.