Ability to use custom session id generation algorithms

New submission from nazgul <None>:

Currently, Site.makeSession() generates session ids via Site._mkuid() and the algorithm in latter is predefined.

Sure one can hack it by overriding Site._mkuid(), but this is a bad practice as I was told.

I suggest there should be a way to pass custom callback function to Site.makeSession(), which then would be called instead of predefined Site._mkuid().

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Type     : enhancement
Component: web
Keywords : 
Priority : normal
Nosy     : 
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http://twistedmatrix.com/trac/ticket/4123