Add Testify MIT license to LICENSE.txt file (#92)

* Add Testify MIT license to LICENSE.txt file

* Add Testify MIT license to LICENSE.txt file
diff --git a/LICENSE.txt b/LICENSE.txt
index d645695..191be87 100644
--- a/LICENSE.txt
+++ b/LICENSE.txt
@@ -200,3 +200,11 @@
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
+
+============
+MIT licenses
+============
+
+This distribution depends on the following components, which are available under an MIT License (https://opensource.org/licenses/MIT).
+
+Testify 1.2.1 (https://github.com/stretchr/testify)
diff --git a/licenses/LICENSE-testify.txt b/licenses/LICENSE-testify.txt
new file mode 100644
index 0000000..f38ec59
--- /dev/null
+++ b/licenses/LICENSE-testify.txt
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2012-2018 Mat Ryer and Tyler Bunnell
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.