Build: Add XCB_LIBS; Skeleton: mlo_initializeInd, mlo_attachDeviceReq

* Renamed some of the Sense API lib classes
  (CSensorDeviceDesc=>CSenseDeviceDesc,
  SensorDeviceDesc=>SenseDeviceDesc).
* Moved SenseApiDesc into /include/user/senseApiDesc.
* Add conversion constructor to convert from SenseDeviceDesc
  to
* Wireframe mlo_initializeInd to call xcb_connect().
* Add $(XCB_LIBS) to libxcbXorg_LDFLAGS.
* Wireframe mlo_attachDeviceReq().

m4/sense_api_opts.m4

@@ -14,6 +14,8 @@ AC_ARG_ENABLE([senseapi-xcbxorg],
                 AC_MSG_ERROR(m4_normalize([XCB library not found. Sense API
                     XCB/Xorg requires the XCB dev headers and shlib.]))
             ])
+            AC_SUBST([XCB_CFLAGS])
+            AC_SUBST([XCB_LIBS])
         ]
     )],
     [enable_senseapi_xcbxorg=no]