improving web text editor: added TextPreviewer and LaTeX symbols to common, some fixes for DynamicTextProcessor  

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30352 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
symbol table popup styling changes

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30353 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
allow painting of TextPreview EV (temporary hack)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30354 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e