runtests: Don't start if linuxcnc or hal is already running
tests/linuxcncrsh: skip this test until we know what's up
Revert "runtests: Don't start if linuxcnc or hal is already running"

This reverts commit 0cc034c6e81873b627204904adf1c681ac8370cb.

The lockfile is currently inadequate, because it provides no way to
check if it's stale or not.  If linuxcnc crashes or otherwise doesn't
get to shut down cleanly, then the lock file will remain but be stale.
docs: add subsections for servos & steppers

The AXIS_n section of the INI docs was a bit confusing.  It started
with generic ini variables applicable to all axis configs, then had a
subsection for homing.  In the homing section it then continued with
ini variables for servos and steppers.  This was confusing.

This commit adds a subsection for Servos and one for Steppers, after
the Homing subsection.  Hopefully this will be clearer.
skip all the tests that use linuxcncrsh

There is some strange bug lurking in linuxcncrsh that causes these tests
to sometimes hang.  I'm disabling them until I figure out what's wrong.
run nc correctly

The -z argument turns on "scan for listeners" mode, which turns off
"pass traffic" mode.  This is true on both netcat-traditional (which is
the default netcat in Ubuntu Precise) and in netcat-openbsd, which is
the other one that's available in Precise.

Ahem.  ;-)
Merge remote-tracking branch 'origin/v2.5_branch' into rtos-integration-preview3
hostmot2: fix compilation warning

Signed-off-by: Michael Geszkiewicz <micges@wp.pl>
Merge remote-tracking branch 'origin/v2.5_branch' into rtos-integration-preview3