Table headers should not generate a double border
add a small fix to the slider thumb border color
web: Align the server avatar image in the space provided

Use a backgroud-image to do this, as it's the simplest. Note that
we now have a standard height of the area. But that makes sense anyway.

Fixes #339
Closes #368

Reviewed-by: Patrick Uiterwijk <puiterwijk@redhat.com>
Alignments of table items and dropdown button

Fixes #349

Reviewed-by: Stef Walter <stefw@redhat.com>
web: Consistent debugging and waiting state for docker operations

Expand the functions in DockerClient for each of the level docker
REST actions. Add create(), rm(), rmi().

Add better debugging to all the operations and pages. Enable one of
these in the javascript console:

$cockpit.debugging="docker"
document.cookie="debugging=docker"

Update the waiting state consistently for all actions on images
and containers.

Closes #361
Reviewed-by: Marius Vollmer <marius.vollmer@redhat.com>
web: Replace action buttons on details page when already doing something

If already performing an action on a container, then replace the
action buttons with a throbber.

Besides being much clearer that something is happening, we're able
to prevent error conditions that would result from running multiple
incompatible actions on the same container.

Reviewed-by: Marius Vollmer <marius.vollmer@redhat.com>
web: Remove login spinner.

Fixes #338
Closes #376

Reviewed-by: Stef Walter <stefw@redhat.com>
web: Add checkbox for starting container with terminal or not

Some commands won't run with a terminal, and not all images need
a terminal. So make this an optoin.

Fixes #357