[PyQt] Flexible __init__ and method chaining.

[ukpyr666]

  Direct translation of C++ API results in huge initialization code 
where it can be done with 1 line.
  To decrease initialization code it will be useful if __init__ of PyQt4 
classes can take additional parameters from **kwargs and auto call 
setXXX methods to set them.
  Also setXXX can return self for method chaining.