Added gpio readall support for the Pi 0W.

Added fixed for a few minor things. pin driver for rht03/dht type
sensors. Network stuff is experimental - for now.

for kernels 4.8 onwards.

Some very old stuff might break.

Additional fixes for the ISR code and some tweaks here and
there. I've removed the checks for some operations that might
fail when using the gpiomem interface - which is now the default
way of doing things - if your program segfaults, then you
may need to use sudo on it.

Also affects the Pi v2 which also uses the new Revision
encoding scheme (It was slightly bodged before) This ought
to be relatively future proof, but who knows.

Fixed a minor thing in the examples Makefile
(not that anyone bothers to use it, judging by the emails I get )-:

Also adding in the stuff for /dev/gpiomem with warnings
and information in the gpio manual page (who reads that
though!)

Updated the gpio program to be device tree aware.

help.

We are going to want to introduce a real Debian source package build
system.  But that needs to contain a lot of things in debian/ which
ought not to appear in the .deb made by the existing ad-hoc `./build
debian' arrangements, which we want to keep so as not to unduly
disturb existing users.

So rename the whole debian/ directory to debian-template/ and change
all references in the build system.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>