added feature to detect if a port is used by a plugin or not

Docs/PluginImplementation.md

@@ -26,6 +26,7 @@ plugin
        |___<plugin name>
                 |___ site.yml 
                 |___ hosts
+                |___ ports.json
                 |___ description.txt 
               .
               . 
@@ -70,6 +71,16 @@ main:
       ansible_sudo_pass: password
 ```
 
+## Ports.json 
+The ```ports.json``` file is intended to mention the number of ports required 
+by the plugin.
+
+```
+{
+  "NumOfPorts": <number of ports>
+}
+```
+
 ## Description file
 This is a simple text file used to describe what the module does. 
 When the client is looking at various commands via the ClI.