Dont merge all custom track properties into session JSON

Author: bbimber

jbrowse/src/org/labkey/jbrowse/model/JsonFile.java

@@ -332,8 +332,6 @@ else if (TRACK_TYPES.bed.getFileType().isType(targetFile.getFile()))
                     put(json.getString("category"));
                 }});
             }
-
-            ret.putAll(json);
         }
 
         return ret;