update regression tests to introduce delays between keys

The regression tests were too severe to be compared real life input. I've added delays in between keys. These now pass in browser and in PhantomJS.

I have a branch https://github.com/bsuh/mithril.js/tree/214withregressiontests which is set to an old commit when #214 was occurring with cherry picks of the regression tests. If you run `grunt teste2e` in this branch, the #214 regression test fails.