Remove outside border from Blockly (issue 92).

core/css.js

@@ -134,7 +134,6 @@ Blockly.Css.setCursor = function(cursor) {
 Blockly.Css.CONTENT = [
   '.blocklySvg {',
   '  background-color: #fff;',
-  '  border: 1px solid #ddd;',
   '  overflow: hidden;',  /* IE overflows by default. */
   '}',
 
@@ -315,6 +314,8 @@ Blockly.Css.CONTENT = [
 
   '.blocklyMainBackground {',
   '  fill: url(#blocklyGridPattern);',
+  '  stroke-width: 1;',
+  '  stroke: #c6c6c6;',  /* Equates to #ddd due to border being off-pixel. */
   '}',
 
   '.blocklyMutatorBackground {',