Using asymmetric errors

Goes away from bootstrapping to use asymmetric error bars calculated
form the distribution of chi-squared values. Also implements a better
way to handle the many figures that are created. Also has some
vestigial stuff from the brief period of trying to get stuff from
images. Needs to be cleaned, and badly. Last commit to master before
trying to get stuff to work where I go through the whole process, from
image to photometric redshift.