remove JASYMCA and MATH_PIPER stringtypes

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25772 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Fix #1367

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25773 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e