* Remove IE compatibility mode meta tag from docs, examples, and JS tests as we no longer support IE9 and IE8
* update and remove some IE bits from our supported browser page
* update introduction.md to match
* reword starter template intro
faster and easier to test/develop js functionality not represented in unit tests, and gives us
a playground for interactions, etc.
It also makes it so developing javascript is now decoupled form jekyll, which should make everything
faster and less painful.
This commit also reverts my filter commit 9900771aa7
which broke scrollspy for dropdowns.
