Moved the OTP MIBs that were included in the application to the new
application OTP_MIBs. The OTP MIBs had no real connection to SASL and
it is desirable that the core of Erlang/OTP is not dependent on SNMP.
Own Id: OTP-4686
Renamed unused variables so that they begin with an underscore (_).
There are also release notes for older versions.