deb: move xhc udev rule to the right place

Lintian reminds us that udev rules belong in /lib/udev/rules.d.
French doc update: clarify comp's usage of count and names
:

Signed-off-by: Francis Tisserant <tissf@free.fr>
French doc update: default spindle speed

Signed-off-by: Francis Tisserant <tissf@free.fr>
Merge remote-tracking branch 'origin/2.6'
uspace: make libudev optional

.. it's not available on debian kfreebsd.

Userspace PCI uses libudev to enumerate available PCI devices, and then memory
maps files in /sys to access the device.  Neither libudev nor this /sys interface
exist on debian kfreebsd.
rtapi: disable /proc for kernel 3.10+

Reportedly, classic kernel APIs we used for the /proc filesystem
have been removed in Linux 3.10.  If so, don't even try.

(untested)
hal: disable /proc for kernel 3.10+

Reportedly, classic kernel APIs we used for the /proc filesystem
have been removed in Linux 3.10.  If so, don't even try.

(untested)
rtapi_math: drop unneeded gcc version check

As documented at http://wiki.linuxcnc.org/cgi-bin/wiki.pl?MinimumSoftwareVersions
the oldest platform we're likely to target with linuxcnc 2.7 is Ubuntu 10.04
with gcc 4.4.
rtapi_math: Move inlines out of i386.h

.. otherwise the implementations are not available e.g., on x86_64 in kernel
spcae
fmin/fmax: Correct return value of fmin(finite, nan)

According to C99, in the case that one argmuent is nan, the other
argument is returned.  This case is likely not exercised by our code,
but someday it might be (nan/inf are only forbidden as a value on a pin
or signal; it's not forbidden internally to a realtime component)