Use vector instead of list for filter sets.
Add a filter_set clear function.
Minor whitespace change.
Debug and logging additions/changes.
If --log-mem-usage and othertrace or userreq logging is used,
destruct various items of global state during termination and log
after each one. This is to help debug/track memory usage.
Minor changes to db helpers to aid above.
Use start and end log lines for socketmanager::(De)InitMultiIOHandlerCommon.
Make sure to clear any old extra headers and data on connection init.
This is in the case of leftovers when retrying a connection.