Remove system namespace support again, the code has been merged into procd instead.
This reverts commit
e5c9b0411d7ebc03a9edbdd3a7809f0e0bdb38dd.
Add system namespace which offers various system information like software release, memory and swap info, uptime and load
add ubus iwinfo api (lacks scanning, assoclist, countrylist and txpowerlist yet)