io.reader: added name and doc kwargs
segments: updated file reading

    - added docstrings for read classmethod
    - added LIGO_LW reader for DataQualityDict and modified reader for
      DataQualityFlag to use that
    - clean up Segment* docstring settings
docs: added extra class documentation

    - added documentation of *Dict and TimeSeriesList
timeseries: added docs for TimeSeries*.read
TimeSeries*.read: changed keyword arguments

    - no max/min keyword arguments for multiprocessing, just ``nproc=1``
      to specify how many processes to use
statevector: added read() docstrings, other minors