dockertest.dockercmd: Print full command when not quiet

Instead of `docker run` print `docker run -t -i ...`. The length is
almost the same but the value of actual command is great.

With this patch the output looks like this:
quiet: (nothing)
nonverbose: Executing: docker run -t -i fedora bash
verbose: Execute docker run -t -i fedora bash
         (program is running)
         Command: ...
         Executed: ...
         ...

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
subtests.docker_cli.kill: Pylint cleanup

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
subtests.docker_cli.kill: Fix incorrect Ouput() usage and dkrcmd verbosity

Previously some dkrcmd.stdouts were replaced by Output(), which by
default resets the output (sets the index at the end of the output).
In logs no lines were printed (as no new lines occured after the call.
This patch adds the possibility to set idx and fixes this issue.

Additionally it replaces all Q*DockerCmds for non-verbose ones, whose
behavior was modified to suit (not only) this purpose.

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
subtests.docker_cli.kill: Add go_lang_bad_signals test

This patch adds new test, which focuses on bad signals caused by golang
bug. Also it removes these signals from all other subtests.

This subtest is intended to be made dependent on the golang bug
and when it's resolved, we can start testing these signals.

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
subtests.docker_cli.kill: Add run_sigproxy_stress_parallel

This test does the same as parallel_stress only it sends the signals
using sigproxy (signals directly to process)

NOTE: Currently this test generates couple of bugs (usually container
crash, sometimes daemon crash)

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
subtests.docker_cli.kill: Add sigstop_sigproxy test

This test is similar to sigstop tests, only it uses sigproxy to send
the signals. The behavior is not always the same thus it's necessarily
to test booth ways.

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
Merge pull request #235 from ldoktor/kill

subtests.docker_cli: Update and add couple of new kill tests