Inversion actual/expected in isEqualTo error message [Issue #201]

Actual and expected were inverted when formatting message since
"expected:\n<%s>\n but was:\n<%s>" changed to "\nExpecting:\n <%s>\nto be
equal to:\n <%s>\nbut was not." in 3dfe40e43bd24bd2f4d3ef394d0bda6d2b5d806e. 
It was only happening when JUnit was not available in classpath.