Enabled Billing Plans and Agreements APIs

- Added API Classes, Samples, and Tests
- Updated Functional Tests
- Updated Documentation with new SDK Name
- Updated Few Samples to use newer nicer result page

tests/PayPal/Test/Functional/resources/BillingPlansFunctionalTest/testUpdateChangingState.json

@@ -0,0 +1,39 @@
+{
+    "description" : "This operation changes the state of billing plan to active if its in created state.",    
+    "title" : "Patch Request for changing state",
+    "runnable" : true, 
+    "operationId" : "plan.update", 
+    "user" : { 
+        "scopes" : ["https://uri.paypal.com/services/subscriptions" ]  
+    },
+    "credentials" : {  
+        "oauth": {
+            "path" : "/v1/oauth/token",  
+            "clientId":"",    
+            "clientSecret":""
+        }
+    },
+    "request" : {
+        "path" : "v1/payments/billing-plans/{PLAN-ID}/",
+        "method" : "PATCH",
+        "headers" : {},
+        "body" : 
+        [
+	   {
+	     "op":"replace",
+	     "path":"/",
+	     "value":{
+	       "state":"ACTIVE"
+	     }   
+	   } 
+	]
+    },
+    "response" : {
+        "status" : "200 OK",
+        "headers" : {},
+        "body" : { }
+    }
+}
+
+
+