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- Adds functionality for specifying configuration parameters via a single
argument containing a URI. Rather than specifying potentially a dozen
separate parameters, one can now provide a single string; for example:
"irc+ssl://botchat.freenode.net:6667/mychannel?limit_access_to=me".
- Adds ability to specify default configuration parameters via environment
variable named 'DEFAULT_IRCPDB_URI'.