THRIFT-2434 Missing namespace import for php TMultiplexedProcessor implementation

Patch: Mauro Maggi
diff --git a/lib/php/lib/Thrift/TMultiplexedProcessor.php b/lib/php/lib/Thrift/TMultiplexedProcessor.php
index 9146ab6..c62e325 100644
--- a/lib/php/lib/Thrift/TMultiplexedProcessor.php
+++ b/lib/php/lib/Thrift/TMultiplexedProcessor.php
@@ -22,6 +22,7 @@
 
 namespace Thrift;
 
+use Thrift\Exception\TException;
 use Thrift\Protocol\TProtocol;
 use Thrift\Protocol\TMultiplexedProtocol;
 use Thrift\Protocol\TProtocolDecorator;