changed stopType (string) parameter to breakOnInfix (boolean)
renamed rewriteInfixNodes to handleInfixNodes
added a test for {1 \over 2} \over 3, fixed some grammar, and added code in the parser to squash superfluous ordgroups
removed squashOrdGroups and instead don't create an "ordgroup" if one already exists
removed unnecessary variable
moved variable declarations out of "if" statements
removed comment
Fixed style issue with where variables are declared and remove unnecessary comment from functions.js