cpp_headers: Renamed C++ headers from .h -> .hpp

To make room for UPM C and C++ sensor code to coexist, all UPM
C++ headers have been renamed from h -> hpp.  This commit contains
updates to documentation, includes, cmake collateral, examples, and
swig interface files.

    * Renamed all cxx/cpp header files which contain the string
    'copyright intel' from .h -> .hpp (if not already hpp).

    * Replaced all references to .h with .hpp in documentation,
    source files, cmake collateral, example code, and swig interface
    files.

    * Replaced cmake variable module_h with module_hpp.

    * Intentionally left upm.h since this file currently does not
    contain code (documentation only).

Signed-off-by: Noel Eck <noel.eck@intel.com>

examples/c++/adafruitms1438.cxx

@@ -25,7 +25,7 @@
 #include <unistd.h>
 #include <signal.h>
 #include <iostream>
-#include "adafruitms1438.h"
+#include "adafruitms1438.hpp"
 
 using namespace std;
 using namespace upm;