Makefiles: Allow setting UIP_CONF_IPV6=0 to work as expected.

Setting UIP_CONF_IPV6 to zero from the make build command line is
something that seems like it should ensure that IPv6 is disabled, but in
fact it actually *enables* IPv6. This seems counter intuitive, so this
patch changes the behavior of the makefiles to handle this case
properly.
Added missing include of contiki-conf.h
Added support for motelist and uploading to Z1 motes under Mac OSX
Remove tab chars from retro C sources.
Merge pull request #92 from oliverschmidt/master

Remove tab chars from retro C sources.
Baudrate now is configured taking into account the MCU frequency, instead of using fixed values for 8MHz freq
Minor README updates.
Merge pull request #96 from oliverschmidt/master

Minor README updates.
removed  tag from z1 Makefile.common
fixed z1 i2c bug where 2 extra bytes were read with every i2c-receive
fixed z1 i2c bug where 2 extra bytes were read with every i2c-receive
Load Makefile.target for slip-radio

This loads Makefile.target into Makefile so we can check for TARGET==sky
when building this. Compilation for sky fails without it.

Signed-off-by: Johannes Gilger <heipei@hackvalue.de>
platform/minimal-net: Implement better idle behavior.

The minimal-net target, as currently written, wakes up the
CPU every millisecond to check for packets, and will only
react in real-time to input from stdin. If you are running
this on a laptop battery, your battery will quickly drain.

This change allows the CPU to idle when there is literally
nothing to do while still being responsive to input from
stein and/or incoming packets. This fix should significantly
improve performance while significantly improving power
usage. Win-win.

Also added `_xassert()` implementation so that the contiki-
provided `assert()` macro will work properly when used
on this platform.
platform/minimal-net: Better, more seamless support for OS X.

This patch enables automatic route setup and cleanup when
starting and stopping the minimal-net target on OS X.

Both IPv4 and IPv6 are supported.

Using the minimal-net target on OS X was absolute hell
before I came up with this patch. Now it is painless.
platform/minimal-net: Print out pseudo LED status.
Do not reject frames with a length exactly equal to the uIP bufer size.
Merge pull request #100 from oliverschmidt/master

Do not reject frames with a length exactly equal to the uIP bufer size.
Have the wget process allow the resolver process to initialize properly.
Merge pull request #103 from oliverschmidt/master

Have the wget process allow the resolver process to initialize properly.
Makes RPL Initial Link Metric configurable