Improve reducedSystem (build smaller systems).
Workaround to correctly format 'reduce'.
Do not set $badStack in browser.
Fix issue 440 and 442.
Partial fix for issue 436.
fix inaccuracy in homogeneousPart, select only lists without common factor
proper definition of homogeneous, add test
Handle tan/atan of constants in normalize.
test guessing facility
Fix issue 441.