[DOCS] Modifies Compatibility statement.

Author: szabosteve

docs/installation.asciidoc

@@ -85,4 +85,6 @@ the next minor release. Support is still incomplete as the API code is generated
 from the {es} Specification that is also still a work in progress.
 
 The {es} Java client is forward compatible; meaning that the client supports 
-communicating with greater or equal minor versions of {es}.
+communicating with greater or equal minor versions of {es}. {es} language 
+clients are only backwards compatible with default distributions and without 
+guarantees made.