For many modules the `Makefile` contains a line like
```
MODULE:=$(shell basename $(CURDIR))
```
This conclusively shows that we do not have to set the module name
manually.
This PR removes the need to set the module name manually, if it is the
same as the basename. E.g. for `…/sys/vtimer/Makefile` the variable
make `MODULE` will still be `vtimer`, because it is the basename of the
Makefile.
Closes#993.
We do not need to descend into the modules to know what to do on
`make clean BOARD=blub`. We can just invoke `rm -rf bin/blub`.
This PR only keeps the descending into the USEPKGs, since they might
want to delete cached/downloaded/extracted data.
Currently the cc2420 and at86rf231 hardware addresses (IEEE 802.15.4
short and long) and frequency channel are read only from a global
variable in the driver. This global variable is only set when the
user sets the address/channel though both parameters might be preset
by the hardware. This change lets the driver read this parameters
directly from the hardware.
