Improve the general quality and functionality of twisted.words.protocols.irc

New submission from jonathanj <None>:

`twisted.words.protocols.irc` appears to be pretty old and not very well maintained:

 * The coding style does not follow the Twisted standard, for the most part.
 * There are many missing docstrings.
 * There is a fairly large amount of code duplication.
 * Test coverage is patchy.
 * Existing tests are of relatively poor quality.
 * Server and client functionality is on a pretty basic level.

Related tickets: #3840, #3285

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Type     : enhancement
Component: words
Keywords : 
Priority : normal
Nosy     : 
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http://twistedmatrix.com/trac/ticket/3841