Add browserstrangeness hacks

[tomkel]

https://github.com/browserstrangeness/browserstrangeness.github.io
https://browserstrangeness.github.io/css_hacks.html

@jeffclayton has added a whole slew of browser hacks to the browserstrangeness site, which are more specific and fill in some gaps in browserhacks. We should merge in his hacks.