Specify time units for default_lock_timeout
Specify time units for default_lock_timeout

Currently, the docstring and sample config entries for
default_lock_timeout do not specify what units of time the value uses
(minutes, seconds, microseconds, etc).  This patch adds units to make
the value easier to understand for operators.

Closes-Bug: #1434620
DocImpact
Change-Id: If6c587e24c13f8ea11725894bfa90a9027e34554

ajayaa/keystone,klmitch/keystone,nuxeh/keystone,mahak/keystone,openstack/keystone,nuxeh/keystone,jonnary/keystone,jonnary/keystone,dstanek/keystone,himanshu-setia/keystone,rajalokan/keystone,idjaw/keystone,cernops/keystone,nuxeh/keystone,roopali8/keystone,mahak/keystone,rajalokan/keystone,ilay09/keystone,jumpstarter-io/keystone,roopali8/keystone,jamielennox/keystone,ilay09/keystone,jumpstarter-io/keystone,takeshineshiro/keystone,mahak/keystone,jamielennox/keystone,himanshu-setia/keystone,openstack/keystone,openstack/keystone,dstanek/keystone,rajalokan/keystone,takeshineshiro/keystone,maestro-hybrid-cloud/keystone,vivekdhayaal/keystone,vivekdhayaal/keystone,idjaw/keystone,ajayaa/keystone,maestro-hybrid-cloud/keystone,cernops/keystone,vivekdhayaal/keystone,dims/keystone,dims/keystone,klmitch/keystone,dstanek/keystone,jumpstarter-io/keystone,ilay09/keystone