Rework application launch code to only use a application manifest as start point

Signed-off-by: Simon Busch <morphis@gravedo.de>
Don't if page is still loading when going into stageReady

Signed-off-by: Simon Busch <morphis@gravedo.de>
Also accept application which have a predefined path for their entry point

Signed-off-by: Simon Busch <morphis@gravedo.de>
Merge pull request #5 from webOS-ports/morphis/work

Morphis/work