Copy hello_world to rbe_system_check to allow room for future expansion. (#78)

The original hello_world will be deleted once the docs are all updated.
diff --git a/examples/remotebuildexecution/rbe_system_check/cc/BUILD b/examples/remotebuildexecution/rbe_system_check/cc/BUILD
new file mode 100644
index 0000000..5962216
--- /dev/null
+++ b/examples/remotebuildexecution/rbe_system_check/cc/BUILD
@@ -0,0 +1,25 @@
+# Copyright 2016 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+package(default_visibility = ["//visibility:public"])
+
+cc_binary(
+    name = "rbe_system_check",
+    srcs = ["rbe_system_check.cc"],
+)
+
+cc_test(
+    name = "rbe_system_check_test",
+    srcs = ["rbe_system_check.cc"],
+)
diff --git a/examples/remotebuildexecution/rbe_system_check/cc/rbe_system_check.cc b/examples/remotebuildexecution/rbe_system_check/cc/rbe_system_check.cc
new file mode 100644
index 0000000..70bd52b
--- /dev/null
+++ b/examples/remotebuildexecution/rbe_system_check/cc/rbe_system_check.cc
@@ -0,0 +1,20 @@
+// Copyright 2016 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <iostream>
+
+int main(int argc, char** argv) {
+  std::cout << "System OK" << std::endl;
+  return 0;
+}