T2966
Depends on D13351
Introduce new function + unit tests, getAliasStringsFromValidAliases, which parses all valid alias tx objects stored in the database and returns an array containing only the valid aliases as strings
Introduce a new function + unit tests, getUnprocessedValidAliasRegistrations, which parses unprocessedTxs and and an array of already registerd aliases, and determines which aliases are valid