Tobiko requires keystone admin endpoint to be created. It was disabled
to be created by default in Devstack by [1].
This patch forces this option to be enabled when tobiko is going to be
installed by devstack.
[1] b538b3267c
Change-Id: I62a25e3de2db8b0aab42eac34bc881822177db15
devstack [1] bash code requires using True and False instead
of true and false
[1] https://opendev.org/openstack/devstack
Change-Id: Ic5fe9fd2141423b45870479e9107e766a3554288
