images: added more images and modified respective header files

Signed-off-by: Sisinty Sasmita Patra <sisinty.s.patra@intel.com>
Signed-off-by: Mihai Tudor Panu <mihai.tudor.panu@intel.com>

src/zfm20/zfm20.h

@@ -83,6 +83,9 @@ namespace upm {
      * This example demonstrates how to register and store a new fingerprint
      * @snippet zfm20-register.cxx Interesting
      * This example demonstrates reading a fingerprint and locating it in the DB
+     *
+     * @image html zfm20.jpg
+     *
      * @snippet zfm20.cxx Interesting
      */
   class ZFM20 {