Add random reply chance to markov bot

Whenever someone says something, there's a chance that markov will
interject his opinion. Users can also set the chance between 0.0 and the
default value (in the config) if they want to see markov replies less
often.

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

tools/markov_import.py

@@ -38,8 +38,9 @@ async def main():
             for line in lines:
                 if mat := LINE_RE.search(line):
                     name = mat["name"]
-                    message = mat["message"]
-                    plugin.add(channel, name, message)
+                    message = mat["message"].strip()
+                    if name != server_config.nick and message and message[0] != "!":
+                        plugin.add(channel, name, message)
     await plugin.save()