Added PSR-4 compatible autoloader as defined at http://www.php-fig.org/psr/psr-4/.

SurfaceActiveCall.php was split into four files. Each file must contain exactly one PHP class because of the following line in the spec:

> The terminating class name corresponds to a file name ending in .php. The file name MUST match the case of the terminating class name.

Other changes were made to correctly import the library using the autoloader.
	Change on 2015/01/02 by mlumish <mlumish@google.com>
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=83150065
diff --git a/src/php/lib/Grpc/SimpleSurfaceActiveCall.php b/src/php/lib/Grpc/SimpleSurfaceActiveCall.php
new file mode 100755
index 0000000..f352573
--- /dev/null
+++ b/src/php/lib/Grpc/SimpleSurfaceActiveCall.php
@@ -0,0 +1,39 @@
+<?php
+namespace Grpc;
+
+require_once realpath(dirname(__FILE__) . '/../autoload.php');
+
+/**
+ * Represents an active call that sends a single message and then gets a single
+ * response.
+ */
+class SimpleSurfaceActiveCall extends AbstractSurfaceActiveCall {
+  /**
+   * Create a new simple (single request/single response) active call.
+   * @param Channel $channel The channel to communicate on
+   * @param string $method The method to call on the remote server
+   * @param callable $deserialize The function to deserialize a value
+   * @param $arg The argument to send
+   * @param array $metadata Metadata to send with the call, if applicable
+   */
+  public function __construct(Channel $channel,
+                              $method,
+                              callable $deserialize,
+                              $arg,
+                              $metadata = array()) {
+    parent::__construct($channel, $method, $deserialize, $metadata,
+                        \Grpc\WRITE_BUFFER_HINT);
+    $this->_write($arg);
+    $this->_writesDone();
+  }
+
+  /**
+   * Wait for the server to respond with data and a status
+   * @return [response data, status]
+   */
+  public function wait() {
+    $response = $this->_read();
+    $status = $this->_getStatus();
+    return array($response, $status);
+  }
+}