[REEF-1909] Fix Compilation errors in VSC++ 2013 and 2015

JIRA: [REEF-1909](https://issues.apache.org/jira/browse/REEF-1909)

This closes #1398
diff --git a/lang/cs/Org.Apache.REEF.Bridge/InteropUtil.cpp b/lang/cs/Org.Apache.REEF.Bridge/InteropUtil.cpp
index 9618485..c569dd6 100644
--- a/lang/cs/Org.Apache.REEF.Bridge/InteropUtil.cpp
+++ b/lang/cs/Org.Apache.REEF.Bridge/InteropUtil.cpp
@@ -135,7 +135,7 @@
   return NULL;
 }
 
-thread_local JNIEnv *t_env = NULL;
+__declspec(thread) JNIEnv *t_env = NULL;
 JNIEnv* RetrieveEnv(JavaVM* jvm) {
   if (NULL == t_env)
   {