Move most CF attrributes outside of CF constructor
Move most CF attrributes outside of CF constructor

These ColumnFamily attributes are still handled if passed as
kwargs to the constructor, but the documentation and code
structure has been shifted to emphasize that they are modifiable
attributes that do not need to be supplied at constrution
time.

The attributes include dict_class, timestamp, buffer_size,
read_consistency_level, write_consistency_level, autopack_names,
and autopack_values.

pycassa/pycassa,pycassa/pycassa