updated default project

* use RIOT submodule and fix an include for the default project
* made default project ready for nativenet
* use config only for MSBA2 in default project
use RIOT submodule and fixed output of hello-world project
use submodule and fixed LED control in hello-world-blinker
use submodule in pingpong
use RIOT submodule for pingpong_sync
use RIOT submodule for tlayer project
use RIOT submodule for sixlowpan project
adapted tlayer project to current RIOT version