In order to fix issue with TPS in hystrix-dashboard threadpool section, removing average calculation for propertyValue_metricsRollingStatisticalWindowInMilliseconds. This was done for hystrixCommand.js previously but not for hystrixThreadpool.js.

* brainlessly apply this : https://github.com/Netflix/Hystrix/commit/892f6a781e67f153b0bf2f7387c87ca0721955c2

fixes gh-1113

See https://github.com/Netflix/Hystrix/issues/1251

Fixes gh-1076

It still isn't actually used (and would only be used on a link to
a non-existent JSP page), but at least it can render now.

See gh-628

Fixes gh-628

see https://github.com/Netflix/Hystrix/pull/927

Also brings in patches to the hystrix dashboard.

fixes gh-465

fixes gh-300

I didn't see a way to do this without dynamic rendering, so
now we have a freemarker dependency (not huge I guess).

Fixes gh-51