fix include names

cppcheck isn't smart enough to recognize these are c++ headers, not c
headers.  Considering we're already inconsistent about our naming, it's
easier to just be consistent, and move the last few files to use .hpp
instead of .h.

Tested:
Code builds, no changes.

Signed-off-by: Ed Tanous <ed@tanous.net>
Change-Id: Ic348d695f8527fa4a0ded53f433e1558c319db40
diff --git a/include/redfish_v1.hpp b/include/redfish_v1.hpp
index 1e4bd65..4230b5f 100644
--- a/include/redfish_v1.hpp
+++ b/include/redfish_v1.hpp
@@ -1,6 +1,6 @@
 #pragma once
 
-#include <app.h>
+#include <app.hpp>
 
 namespace crow
 {