minor fixes
Renaming folders (step 1)

Git is not a big fan of renaming things to an uppercase version. So we
do the following:
foldername --> _foldername
COMMIT
_foldername --> Foldername
COMMIT
Renaming folders (step 2)
Removed some minor methods

complex.p.mod
polynomial.p.content
polynomial.p.isPrimitive
polynomial.p.isReal
polynomial.p.mod
added some links, splitted polynomial and complex test files