Removing Dependency from SDK Core Project

- Copied files required for Rest API SDK
- Removed PPApiContext and directly connected APIContext with PPConfigManager
- Removed duplicate data storage of configuration and credentials.
- Code Style Fixes
- Remove build.xml file as it is not required anymore
- Updated the samples
- Updated the documentations

tests/PayPal/Test/Exception/PPConnectionExceptionTest.php

@@ -0,0 +1,48 @@
+<?php
+use PayPal\Exception\PPConnectionException;
+/**
+ * Test class for PPConnectionException.
+ *
+ */
+class PPConnectionExceptionTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @var PPConnectionException
+     */
+    protected $object;
+
+    /**
+     * Sets up the fixture, for example, opens a network connection.
+     * This method is called before a test is executed.
+     */
+    protected function setUp()
+    {
+        $this->object = new PPConnectionException('http://testURL', 'test message');
+        $this->object->setData('response payload for connection');
+    }
+
+    /**
+     * Tears down the fixture, for example, closes a network connection.
+     * This method is called after a test is executed.
+     */
+    protected function tearDown()
+    {
+    }
+
+    /**
+     * @test
+     */
+    public function testGetUrl()
+    {
+    	$this->assertEquals('http://testURL', $this->object->getUrl());
+    }
+    
+    /**
+     * @test
+     */
+ 	public function testGetData()
+    {
+    	$this->assertEquals('response payload for connection', $this->object->getData());    	
+    }
+}
+?>