Updated installation doc with Composer

Soap/SoapAttachment.php

@@ -37,4 +37,4 @@ class SoapAttachment
     {
         return $this->content;
     }
-}
+}

Soap/SoapClientBuilder.php

@@ -74,4 +74,4 @@ class SoapClientBuilder extends BaseSoapClientBuilder
             ));
         }
     }
-}
+}

Soap/SoapHeader.php

@@ -47,4 +47,4 @@ class SoapHeader
     {
         return new \SoapHeader($this->namespace, $this->name, $this->data);
     }
-}
+}

Soap/SoapRequest.php

@@ -164,4 +164,4 @@ class SoapRequest extends Request
 
         return $result;
     }
-}
+}

Soap/SoapResponse.php

@@ -66,4 +66,4 @@ class SoapResponse extends Response
     {
         return $this->soapReturnValue;
     }
-}
+}