InEpsilonSlice doesn't print the message

[pkaeding]

InEpsilonSlice is implemented as a series of calls to InEpsilon (which is not unexpected), but when it calls InEpsilon, it does not pass the msgAndArgs ...interface{}. As a result, the failures are not very helpful, because the default output of InEpsilon only tells the relative error, not the expected & actual values.

It isn't immediately obvious to me how InEpsilonSlice should deal with the messages when calling InEpsilon-- especially if there are multiple mismatches, would you want to print the same message each time?