Fix typos in field names

The field names of certain documents contained typographical errors, making it
impossible to retrieve this data from the onionoo-backend. Fixed according to
https://onionoo.torproject.org/protocol.html
Add missing fields to RelayWeight

This document was missing two fields present in the protocol specs.
Added according to https://onionoo.torproject.org/protocol.html
Add bridge uptime object

There was no object for retrieval of this document's data. Added according to
https://onionoo.torproject.org/protocol.html