add -U option to copy .pkg to cache & install it
add -U option to copy .pkg to cache & install it

Signed-off-by: Chris “Kwpolska” Warrick <de6f931166e131a07f31c96c765aee08f061d1a5@gmail.com>

mfussenegger/pkgbuilder,Kwpolska/pkgbuilder,Kwpolska/pkgbuilder,mfussenegger/pkgbuilder