[BUGFIX beta] Fix IE 6/7 RenderBuffer issue

IE 6/7 has a bug that prevents the 'name' attribute from being properly set on
an 'input' created with 'createElement'. This provides a workaround by using IE
specific `createElement` behavior that allows a tag string to be passed to
`createElement` instead of just a tagName.

Fixes #3525
Merge pull request #3553 from wagenet/ie-render-buffer-fix

Fixes to RenderBuffer for IE6/7 - Fixes #3525