VOL-3616: Add support for GetSingleValue RPC

Change-Id: I87d0f3e5a158e2062ae15993db272aaf38c59765
diff --git a/VERSION b/VERSION
index 0cadbc1..da6b0a8 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.5.5
+2.5.6