classes: add simple bbclass to extend package meta data for device/luna restart

Signed-off-by: Simon Busch <morphis@gravedo.de>
org.webosinternals.service.update: package needs a device restart after an upgrade

Signed-off-by: Simon Busch <morphis@gravedo.de>
classes: rename cordova_application/enyojs_application bbclass to start with prefix webos_

Signed-off-by: Simon Busch <morphis@gravedo.de>
classes: move common application parts from webos_enyojs_application into own webos_application class

Signed-off-by: Simon Busch <morphis@gravedo.de>
org.webosports.app.pdf: add pdf viewer application

Signed-off-by: Simon Busch <morphis@gravedo.de>