Allow IFactor in input bar

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@27797 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Simplified code

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@27798 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Compile error

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@27799 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Simplified code

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@27800 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e