Add function to format the data for the biplots
Change format to be clearer in HTML output
Add sort module and tests module to emperor

This module currently aids with the sorting that should take place
when operating otu tables from the script interface.

The all variable in the __init__.py file is now updated.
Fix bug in preprocess_otu_table

This bug caused the biplot information to be placed in the exact
coordinates where samples were positioned. This function now makes use
of emperor.sort to make sure that the sample identifiers match between
coordinates files and otu tables.

The script interface was updated accordingly since the filtering of the
otu table is now performed using the header in the coordinates data.