Provide simple drawing for TObjString (#164)

Author: linev

scripts/JSRootPainter.js

@@ -5523,7 +5523,7 @@
       }
 
       painter.Draw = function() {
-         var txt = this.txt.value;
+         var txt = (this.txt._typename && (this.txt._typename == "TObjString")) ? this.txt.fString : this.txt.value;
          if (typeof txt != 'string') txt = "<undefined>";
 
          var mathjax = this.txt.mathjax || (JSROOT.gStyle.Latex == 4);
@@ -5641,6 +5641,7 @@
    JSROOT.addDrawFunc({ name: "TWebPainting", icon: "img_graph", prereq: "more2d", func: "JSROOT.Painter.drawWebPainting" });
    JSROOT.addDrawFunc({ name: "TPadWebSnapshot", icon: "img_canvas", func: JSROOT.Painter.drawPadSnapshot });
    JSROOT.addDrawFunc({ name: "kind:Text", icon: "img_text", func: JSROOT.Painter.drawRawText });
+   JSROOT.addDrawFunc({ name: "TObjString", icon: "img_text", func: JSROOT.Painter.drawRawText });
    JSROOT.addDrawFunc({ name: "TF1", icon: "img_tf1", prereq: "math;more2d", func: "JSROOT.Painter.drawFunction" });
    JSROOT.addDrawFunc({ name: "TF2", icon: "img_tf2", prereq: "math;hist", func: "JSROOT.Painter.drawTF2" });
    JSROOT.addDrawFunc({ name: "TSpline3", icon: "img_tf1", prereq: "more2d", func: "JSROOT.Painter.drawSpline" });