Performance Improvements

Significant improvements to the runtime of core XPath and XForms functions (path resolution, template contextualization, etc).
Hey, apologies, these were from a branch that had tabs that existed before the tab shift. I tried to fix them all during the merge process but the tool missed a few. I tried to sed \t -> four spaces but for some reason that did not seem to result in the files being in the same state pre-merge.