docs(readme) add more development instructions

The different test suites and the way test/development running Kong need
a different configuration file can be confusing at first, so this adds
some more insight as to what is needed and why.

Of course, this is the current system but nothing prevents it from being
improved in the future.

Makefile

@@ -54,4 +54,4 @@ coverage:
 	@rm -f luacov.*
 	@busted --coverage spec/
 	@luacov -c spec/.luacov
-	@tail -n 1 luacov.report.out | awk '{ print $$3 }'
+	@tail -n 1 luacov.report.out | awk '{ print $$3 }'

README.md

@@ -252,7 +252,7 @@ Support, Demo, Training, API Certifications and Consulting available at https://
 ## License
 
 ```
-Copyright 2015 Mashape, Inc
+Copyright 2016 Mashape, Inc
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -277,4 +277,3 @@ limitations under the License.
 [gitter-badge]: https://img.shields.io/badge/Gitter-Join%20Chat-blue.svg
 
 [google-groups-url]: https://groups.google.com/forum/#!forum/konglayer
-