BUG: Fixed a bug in ExpectationMaximiationMixtureModelEstimator.

Because of the bug, the parameters of some Gaussian components are not updated
once the previous components has change. The UpdateParameter function stops
early. After fixing it, the example on the Wiki page works.

Change-Id: Id9701af09722b7c90f37cd8f82a38293b54185d3
Merge branch 'release-FixExpectationMaximizationFilter' into release

Change-Id: I40f7b848b17dd0ff541e36b882b79fb2b92dd461