Allow Input Boxes with no linked geo

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@32891 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
#4112: NPE fix

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@32892 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Only show unfinished languages in prerelease

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@32893 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e