segwizard: added kwargs
Array.from_hdf5: fixed bugs in name parsing
TimeSeriesAxes.set_xlim: fixed bugs in LIGOTimeGPS in xlim
DataQualityDict.{union,intersection}: new combination methods
plotter.SegmentFormatter: improved formatting

    - checks against the plotted segments to see if data exist at a
      given y-axis value
SegmentAxes: fixed inset label y-position
Segment{Axes,Plot}: improved segment labelling

    - labelling now down using draw() override and improved
      SegmentFormatter
SegmentAxes: added plotting for DataQualityDict
DataQualityDict.plot: added dict plotter
DataQualityDict.__or__: fixed bug
TimeSeriesDict.append now returns self
segments: minor doc changes
plotter.utils.rUNDERSCORE: added _ -> \_ regex
gwpy.cli: remove undeveloped submodule
SpectrogramPlot: remove unused variable
SpectrogramPlot: removed default log

    - not user friendly given that it doesn't set ylim automatically as
      well
    - this fixes #20
data: minor docstring change
Merge branch 'master' into sosfilter