Fix use of random.choice

random.choice cannot work with sets, as sets are not indexable
By default, use a random initial state for Aßmann

Using the fixed initial state can be achieved by passing
--fixed-state.
Merge pull request #6 from horazont/random-state

Random state
Make whitespace folder more aggressive

Now folding consecutive whitespaces to a single one
Implement in-place merging of graphs
Implement in-place merging of Markov chains
Implement a merger frontend for Aßmann.py
Implement gajim db source
Rename _source_type function for consistency
Remove legacy test script
Fix typo
Add --contact-name filter
Remove debug statement
Add recursive method to extract plain text parts from mails
Awesomize get_plaintext_parts()
yield message object instead of string representations
Prepare maildir input
_really_ return messages instead of strings
Add maildir_source() that opens mailboxes and handles decoding
Document get_encoding() method