Log current version on startup

We recently got a bug report from someone running Limnoria in Docker, and it turned
out that a plugin's import was segfaulting and Docker silently restarted the process.

I wasted some time figuring out what happened because I didn't notice the process
was being restarted. This should make this more noticeable in the future.

src/scripts/limnoria.py

@@ -76,6 +76,9 @@ from supybot.version import version
 
 def run():
     import supybot.log as log
+
+    log.info("Starting Limnoria %s on Python %s", version, sys.version)
+
     import supybot.conf as conf
     import supybot.world as world
     import supybot.drivers as drivers