Commit 56(Post Beta)

IMPORTANT: This commit corrects an important IE8 bug that was
in the previous commit (55)

This commit also includes some significant updates and improvements:

- New API for creating derived tags - simply specify "baseTag" on
  the custom tag declaration:

  $.views.tags({
    range: {
      // Inherit from {{for}} tag
      baseTag: $.views.tags["for"],
      ...

  See samples: http://www.jsviews.com/#samples/jsr/tags/extend-for
  and http://www.jsviews.com/#samples/tag-controls/range

- Bug fixes:
  https://github.com/BorisMoore/jsrender/issues/238
  https://github.com/BorisMoore/jsviews/issues/267