Form data passed via POST for marker regression

Removed "Use Parents" and "Use Weighted"

Created text box to input # permutations for pair scan
Improved appearance/layout of the interval mapping tab using bootstrap
Continued to customize the interval mapping menu
More changes to the layout of interval mapping options
Made composite mapping options show/hide for the interval mapping section
The control locus field in the interval mapping settings is now disabled if
"choose closest control" is set to "yes"
Changed layout of marker regression options
Created template for marek regression page and made the compute button direct
to it

added asbolute_import in data_set.py and trait.py

Made several minor changes and deleted commented out code in trait.py
marker_regression page is up again
Began working on marker_regression.py and created Chromosomes class
in species.py