Figure out a way to disable IE's Compatibility Mode in the docs and examples

[juthilo]

Bootstrap doesn't support Compatibility Mode in Internet Explorer, so we should probably act accordingly and disable it in the docs and various examples using the appropriate meta tag, as outlined in the docs.

I've done some research on this. Turns out, X-UA-Compatible as a value for http-equiv doesn't pass W3C HTML validation.

This is a common problem. Suggested solutions include sending the information via HTTP headers (which we can't do) and some magic with conditional comments.

Questions:

• Should we (still) try to do this?
• Can we disable certain rules in grunt-html-validation? @seriema ?
• Does anybody have enough experience with this to implement the solution with conditional comments?

I originally just wanted to add this myself but I don't understand the various problems that came up well enough. Let's see if anyone can help! Thanks!

[cvrebert]

I say we do it. The validator is being overly pedantic; we should ignore this particular warning. Failing validation doesn't currently fail Travis anyway, so this won't truly break anything.
Conditional comments would open up another can of worms; I would avoid using them here.

[juthilo]

@cvrebert Ah, I think I mistook a fail due to browserstack for a fail due to validation. That explained a lot already, thanks!

[cvrebert]

Yeah, BrowserStack seems to randomly timeout fairly often. We should bring it up with them. But that's a matter for another issue...