feat(cli): add check command

packagemanager/pacman.go

@@ -74,3 +74,8 @@ func (p *PacmanManager) UpdateAllPackages() error {
 	command.Stdin = strings.NewReader(p.SudoPassword + "\n")
 	return command.Run()
 }
+
+func (p *PacmanManager) Check(pkg string) error {
+	cmd := shell.ExecCommand("/bin/sh", "-c", fmt.Sprintf("paxman -Q | grep %s", pkg))
+	return cmd.Run()
+}