Update the LICENSE to match the 'standard' MIT license file

The reason is that since the name of the license is not stated
explicitly and the license text differed very slightly I had to perform
a diff to ensure it actually is MIT licensed. Also GitHub does not
detect the license for this project currently (probably for the same
reason).

Changes:

* Remove the line 'Please consider promoting this project...' that is
  not part of the MIT license
* Use the same formatting as choosealicense.com
* Explicitly state 'MIT License'
* Update the copyright year

LICENSE

@@ -1,22 +1,21 @@
-Copyright (c) 2012 - 2013 Mat Ryer and Tyler Bunnell
+MIT License
 
-Please consider promoting this project if you find it useful.
+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:
+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 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.
+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.

README.md

@@ -329,3 +329,10 @@ Contributing
 Please feel free to submit issues, fork the repository and send pull requests!
 
 When submitting an issue, we ask that you please include a complete test function that demonstrates the issue.  Extra credit for those using Testify to write the test code that demonstrates it.
+
+------
+
+License
+=======
+
+This project is licensed under the terms of the MIT license.