Wi-SUN mesh API uses now nanostack certificate interface with length parameters.
This enables that either PEM or DER formatted certificates can be used. Using
the length configuration for certificates and keys is optional, so existing
applications using the PEM certificates do not require changes.
Set tasklet parameters before connecting to prevent the parameters to be set to 0.
The tasklet parameters are reset to 0 when wisun_tasklet_connect gets called,
thus those need to be set in the wisun_tasklet_configure_and_connect_to_network
before they are used. This is also done this way in other tasklets.
To get Wi-Sun mesh network working, also nanostack with Wi-Sun support
is needed. ws_empty_functions.c and ws_management_api.h are temporary
included here, so that wisun_tasklet will compiled without problems.
They will replaced with the official versions with next nanostack release.