A major cleanup, disentangling net_if and ssl_if.
Pulled a lot of common logic into the core and reduced size of net_if implementations.
CL: Mongoose net_if and ssl_if refactoring
PUBLISHED_FROM=29bd4dcb264a1fd96b3dd164e2d880e1c2c0921e
freshen: implement ota rollback
freshen: api for rpc
freshen: implement rpc api (without transport)
PUBLISHED_FROM=9f935f676161c81464a0dc53d5d8d085b2437ffb