getEvents - id<=0 now resets server's notion of client's id to last N events (and starts sending there)

Some Python/ssl module versions incorrectly initialize hashlib, causing weird openssl errors. Importing hashlib explicitly helps.

More sensible configuration file defaults, some sections left commented to prevent unnecessary default filtering and/or adding Node info

Logging module in Python 2.6 does not accept unicode socket path - but strings from JSON configuration are always unicode. Applied workaround, now on 2.6 Client accepts at least ASCII filenames for syslog socket.

 * Server is now in line with Idea spec concerning client names - they are stored in db and compared lowercase
 * Fixed duplicity check when adding/modifying client
 * Secret is not secret anyway, simplify Client and logging code

* --pid_file is now on command line, instead of in cfg file (better supports startup shell scripts)
* filer now supports done_dir, where processed messages get stored instead of removing them
* sender now can opportunistically wait if the number of event files to process is lower than send_events_limit. Governed by owait_* cfg file options

* Shorter example config

Export correct time with timezone
Export virus scan report in correct format

Minor updates