Add back the html5-hvac application, adapting installation to the new
application framework:
- It provides a valid .desktop file.
- It does not use the .wgt file, and just deployes to
/usr/lib/wam_apps/html5-hvac the application files.
Bug-AGL: SPEC-4224
Change-Id: Icee2d6bfdbd69265614581b731a76a6742036720 Signed-off-by: Jose Dapena Paz <jdapena@igalia.com>