Add support to unpack archive files

src/args.rs

@@ -132,12 +132,20 @@ pub enum Command {
     },
     /// Import to script
     Import(ImportArgs),
+    /// Pack files to archive
     Pack {
         /// Input directory
         input: String,
         /// Output archive file
         output: Option<String>,
     },
+    /// Unpack archive to directory
+    Unpack {
+        /// Input archive file
+        input: String,
+        /// Output directory
+        output: Option<String>,
+    },
 }
 
 pub fn parse_args() -> Arg {