Allow for offset bin positions
Allow for offset bin positions

This permits splitting of input count data files while preserving the original
(0-offset) chromosome coordinates in Multipool output.

Change function load_table to set a numpy array of integer bin start positions
(in base pairs) from the range of observed locus positions, and include these
in its return value.

Change function doLoading to accept bin start positions from each call to
load_table, pad data to have a consistent bin range for all input tables,
and include bin start positions in its return value.

Change function doOutput to accept bin start positions as a parameter, and print
the start position of the given bin on the first column of each line.

Change function doPlotting to accept bin start positions as a parameter, and set
horizontal plot axes from these.

matted/multipool