Add main method so link.infra.packwiz.installer.Main can be launched directly

Useful for scripts or tools that already handle automatic updates of
packwiz-installer, such as docker-minecraft-server :)
Adds a message to suggest using the bootstrapper for automatic updates

src/main/kotlin/link/infra/packwiz/installer/Main.kt

@@ -135,6 +135,12 @@ class Main(args: Array<String>) {
 			options.addOption("g", "no-gui", false, "Don't display a GUI to show update progress")
 			options.addOption("h", "help", false, "Display this message") // Implemented in packwiz-installer-bootstrap!
 		}
+
+		@JvmStatic
+		fun main(args: Array<String>) {
+			Log.info("packwiz-installer was started without packwiz-installer-bootstrap. Use the bootstrapper for automatic updates! (Disregard this message if you have your own update mechanism)")
+			Main(args)
+		}
 	}
 
 	// Actual main() is in RequiresBootstrap!

src/main/kotlin/link/infra/packwiz/installer/metadata/hash/Hash.kt

@@ -21,7 +21,14 @@ data class Hash<T>(val type: HashFormat<T>, val value: T) {
 
 		object UInt: Encoding<kotlin.UInt> {
 			override fun encodeToString(value: kotlin.UInt) = value.toString()
-			override fun decodeFromString(str: String) = str.toUInt()
+			override fun decodeFromString(str: String) =
+				try {
+					str.toUInt()
+				} catch (e: NumberFormatException) {
+					// Old packwiz.json values are signed; if they are negative they should be parsed as signed integers
+					// and reinterpreted as unsigned integers
+					str.toInt().toUInt()
+				}
 		}
 	}