Merge pull request #1 from milestogo/master

Patch for RFC1918 mesh and AP addresses
try to cleanup after previous partial installs
fix bug with setting ssh authorised key.
improve cleanup code so that repeated running of the 2.*
script can work (some issues remain, but situation is much improved)
work towards nw703n support and adding more useful packages to
USB partition, in particular python for flashing radios.
include upgrade script in extra files for installation in /serval
rebuilt archives of extra files with upgrade script and python
and other goodies.
fixed missing $ in script.
added missing back-quote.
make IP addresses have only 4 octets instead of 5.
added missing end quote.
allow selection of router model for upgrading.
auto-detect router model and IP (if you are on my mac).
auto-detect IP address of router in some cases.
fixed two $1's that should be ${ip} now.
show remaining stuff in /overlay
update package fetching for wr703n
fix missing bin/ directory in extra-files-serval.tgz
refactor installation of mesh extenders to use two staging directories
for config file and directory setup.  stage-1 is pre mounting of USB
and stage-2 is for after USB is mounted.
Also make sure USB file systems are cleaned out if they are hanging around.
add zlib package (had libz by mistake which is libzip.* instead of libz.*)
remove unsupported -ls option to find.
unmount file systems before trying to newfs them.