stretchr/testify — pull request #60 by 2pi (2014-07-01 11:44:48+00:00)
Title: add wrapper around the `EqualError` function

As the title suggests, I have added a wrapper around the `EqualError` function(by mostly copying and pasting) so that `EqualError` can be used when you use the `*Assertions` struct.

Rest of the commit message:
* add a `*Assertions` wrapper around the `EqualError` function
* add tests