When using list_limit configuration option in Default section of
keystone.conf, the /services?name=<service_name> API fails to find
the service if list_limit value is smaller than the total number
of services and the searched service is not among the first
'list_limit' services. The API should first filter by name and
only afterwards truncate the result list.
Also, this patch fixes setting the 'truncated' attribute of the
driver's hint.limit object when truncating the list outside of
driver_hints.truncated decorator, problem exposed by fixing the
problem described in the first paragraph.
Closes-Bug: #1594482
Change-Id: I832f542c3cb0faf94a1e5bce5a894f7f4d26a8de