Fix timezones in line chart

Ceilometer gives us UTC and works with UTC, we should honor that
in line chart, cause we are just passing samples there.

Hover detail of sample should show localized time.

Change-Id: I83c23a13eb27b71e71268bc7b99c0ce0fdd1d59a
Closes-Bug: #1359690
Integration tests - BaseWebObject class

I added BaseWebObject, a base class for all web element objects,
i.e. both page objects and regions.
The new class now contains several wrappers for driver's
capabilities, which are required not only by the pages but other
webelements as well, and used to be located within pageobject.
The necessity arose while discussing the regions patch
(https://review.openstack.org/#/c/102227/), that will be
modified accordingly by tnovacik.

In addition, I've made 6 methods private, as they should
not be used outside the pages, definitely not by the tests.

Partially implements blueprint: selenium-integration-testing
Closes-Bug: #1354017
Closes-Bug: #1356774

Change-Id: Id65951160b2016cbdafd8417df48b1b5cd02f99f
Only enable one images filter button

Only one button for the images filter buttons should be enabled at any one time.
This is solved by removing the active class from all the filter buttons upon
selecting a filter.

Change-Id: I9d7753684f144a6d66ccc5b09f830b360a07a620
Closes-bug: 1365803
Update integration tests password

The new gate job to run the integration tests is currently failing
because the password defined in horizon.conf does not match the
password created for devstack on the gate. It should be updated to
"secretadmin".

Change-Id: I71e37dcc78c2c6d5d7666a6aa466afa84e91629d
Closes-Bug: #1392269
Merge "Integration tests - BaseWebObject class"
Merge "Fix timezones in line chart"
Merge "Only enable one images filter button"
Merge "Update integration tests password"
Merge branch 'master' of https://github.com/openstack/horizon