rename headers to match style

Moving headers from ".h" to ".hpp"

Reworked the header inclusion a bit so that host-ipmid is treated as a
library, and local headers aren't.

renamed apphandler.h => apphandler.hpp
renamed chassishandler.h => chassishandler.hpp
renamed globalhandler.h => globalhandler.hpp
renamed sensorhandler.h => sensorhandler.hpp
renamed storageaddsel.h => storageaddsel.hpp
renamed storagehandler.h => storagehandler.hpp
renamed systemintfcmds.h => systemintfcmds.hpp

Change-Id: I9d4ce3dd57e2e996800f9020a10cc10cdf2c3914
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/fruread.hpp b/fruread.hpp
index 20f260c..a2fb650 100644
--- a/fruread.hpp
+++ b/fruread.hpp
@@ -1,5 +1,4 @@
-#ifndef OPENBMC_IPMI_FRU_READ_H
-#define OPENBMC_IPMI_FRU_READ_H
+#pragma once
 
 #include <systemd/sd-bus.h>
 
@@ -35,5 +34,3 @@
 
 using FruId = uint32_t;
 using FruMap = std::map<FruId, FruInstanceVec>;
-
-#endif