feat(HtmlParser): enforce only void & foreign elts can be self closed

BREAKING CHANGE:

`<whatever />` used to be expanded to `<whatever></whatever>`.
The parser now follows the HTML5 spec more closely.
Only void and foreign elements can be self closed.

Closes #5591

modules/angular2/test/compiler/template_parser_spec.ts

@@ -728,8 +728,8 @@ Parser Error: Unexpected token 'b' at column 3 in [a b] in TestComp@0:5 ("<div [
           type: new CompileTypeMetadata({name: 'DirB'}),
           template: new CompileTemplateMetadata({ngContentSelectors: []})
         });
-        expect(() => parse('<div/>', [dirB, dirA])).toThrowError(`Template parse errors:
-More than one component: DirB,DirA ("[ERROR ->]<div/>"): TestComp@0:0`);
+        expect(() => parse('<div>', [dirB, dirA])).toThrowError(`Template parse errors:
+More than one component: DirB,DirA ("[ERROR ->]<div>"): TestComp@0:0`);
       });
 
       it('should not allow components or element bindings nor dom events on explicit embedded templates',