bugfix: comma --> semicolon

git-svn-id: https://fricas.svn.sourceforge.net/svnroot/fricas/trunk@1692 b0c55286-4f34-0410-a049-a1e7e93b0762
Decouple SExpression and OutputForm.


git-svn-id: https://fricas.svn.sourceforge.net/svnroot/fricas/trunk@1693 b0c55286-4f34-0410-a049-a1e7e93b0762