- optimized a couple of invariant expressions - made sure solveCubic() also works when called with integer arguments
- optimized a couple of invariant expressions
- made sure solveCubic() also works when called with integer arguments


git-svn-id: 05b73559aeb8bace4cf49b5ea964569f1305eff8@398 4cde692c-a291-49d1-8350-778aa11640f8

fonttools/fonttools,googlefonts/fonttools