Update According to Review Comments #397

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semaphore/README.md

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+---
+layout: pattern
+title: Semaphore
+folder: semaphore
+permalink: /patterns/semaphore/
+categories: Lock
+tags: 
+ - Java
+ - Difficulty-Beginner
+---
+
+## Also known as
+Counting Semaphore
+
+## Intent
+Create a lock which mediates access to a pool of resources. 
+Only a limited number of threads, specified at the creation 
+of the semaphore, can access the resources at any given time.
+A semaphore which only allows one concurrent access to a resource
+is called a binary semaphore.
+
+![alt text](./etc/semaphore.png "Semaphore")
+
+## Applicability
+Use a Semaphore when 
+
+* you have a pool of resources to allocate to different threads
+* concurrent access to a resource could lead to a race condition 
+
+## Credits
+
+* [Semaphore(programming)] (http://en.wikipedia.org/wiki/Semaphore_(programming))
+* [Semaphores] (http://tutorials.jenkov.com/java-concurrency/semaphores.html)