Ticket #3337: handle data-param-width and data-param-height (basic)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@27024 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Ticket #3337: small improvements (basic)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@27025 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e