Reworked error handling in server, client and filer (again :( ). We definitely have to support multiple errors so let's do it right.  Error now contains list of errors.  Got rid of "detail" section everything now goes directly within particular error.  Error can bear "events" attribute for list of sent events concerned (or none if all sent events erred). Streamlined error logging.
Server now retries if MySQL went away.
Response result now gets properly encoded if Unicode appears somehow (however that's just fighting symptoms, should get more thorough fix).

syntax highlighting. :) (deja-vu)

syntax highlighting. :)

  consistently. Possible keeping and reopening where possible will need more
  work and testing, I'm not keen to try to clench in now. So - changed to
  reopening connection each time, which will possibly affect performance (on
  small queries).
- Both server and client library now defaults to get_events_limit instead of 1

Fixed Recon id in catmap
Fixed isoformat calling on None
Shortened validation error message
Fixed rejecting of Test messages

Added optional client auth by shared secret (also modified schema, client, curl client). Modified Client __str__ method for log display without disclosing secret. Modified wsgi server logging and parameter disposing accordingly.

Clients are now authorized by client= argument in URL, schema and client lib is updated accordingly. Method authentication defined in "expose" decorator. Added Client container class for deterministic logging. Schema update to consistent InnoDB and utf8mb4 everywhere.

Error is now raised via req.error helper, which automatically adds already known info (method, request id), thus calls are terser.
Client's Error communicates request id, if received from server.
exc_info made explicit everywhere. Automatic exc_info gathering sometimes returned bogus info about unrelated exception from far before.

Fixed multiple HTTP args encoding/parsing, store_event now uses SQL placeholders, more robust fetching of cat/tag in store_event, simplified map_id usage