Fix incorrect ca arguments for calling ceilometer client

With ceilometer configured with SSL, Horizon fail to connect to
ceilometer to load the meters(usage data) due to it passed a wrong
of ca argument for ceilometer client. Should use 'cacert' instead
of 'ca_file'.

See ceilometer client:
https://github.com/openstack/python-ceilometerclient/blob/master/ceilometerclient/v2/client.py#L53

Change-Id: I296c61119e07cd2e19079ef62054c5837fa13114
Closes-Bug: #1388764
Imported Translations from Transifex

For more information about this automatic import see:
https://wiki.openstack.org/wiki/Translations/Infrastructure

Change-Id: I8bcd3f20a841755924226a7aba469346ac44ddc4
Updated from global requirements

Change-Id: Iaaca3a72978b17daea6083708cfa602245f6d501
Merge "Updated from global requirements"
Merge "Imported Translations from Transifex"
Merge branch 'master' of https://github.com/openstack/horizon