Install packages from queue

def install(self):
        """Install packages from queue
        """
        packages = self.packages()
        if packages:
            print("")   # new line at start
            for pkg in packages:
                ver = SBoGrep(pkg).version()
                prgnam = "{0}-{1}".format(pkg, ver)
                if find_package(prgnam, self.meta.output):
                    binary = slack_package(prgnam)
                    PackageManager(binary).upgrade(flag="--install-new")
                else:
                    print("\nPackage {0} not found in the {1} for "
                          "installation\n".format(prgnam, self.meta.output))
        else:
            print("\nPackages not found in the queue for installation\n")
            raise SystemExit(1)