Implement ManifestDirectInstall and ManifestDirectUpdate request handling

Implement ManifestDirectInstall and ManifestDirectUpdate request handling

To verify, try following to scenarios:

1)
 wgt-backend -i ${package}
 wgt-backend -y ${pkgid} # package should be updated from its manifest with success

2)
 wgt-backend -i ${package}
 rm /home/$USER/.applications/dbspace/*
 wgt-backend -y ${pkgid} # package should be installed from its manifest with success

Submit together:
 https://review.tizen.org/gerrit/#/c/64204

Change-Id: I47c2af1e71e8f9b0f022c593762644da88afb8f9