packageDependencies support raw url

[hongweiyi]

We company have built a private git repository, so we want add private packageDependencies in package.json

Usage:

"packageDependencies": {
        "about": "CodeboxIDE/package-about",
        "command-palette": "CodeboxIDE/package-command-palette",
        "myPackage": "git@gitlab.domain.com:hongweiyi/package-myPackage.git"
}