python 3 port: /!\ Python 3.6+ is now needed to use libervia /!\ instability may occur and features may not be working anymore, this will improve with time /!\ TxJSONRPC dependency has been removed The same procedure as in backend has been applied (check backend commit ab2696e34d29 logs for details). Removed now deprecated code (Pyjamas compiled browser part, legacy blog, JSON RPC related code). Adapted code to work without `html` and `themes` dirs.