add license, move folders

app/scripts/platform.gd

@@ -0,0 +1,42 @@
+extends Node
+class_name Platform
+
+enum {
+	WINDOWS,
+	MACOS,
+	LINUX_BSD,
+	ANDROID,
+	IOS,
+	WEB
+}
+
+
+static func is_windows() -> bool:
+	return get_platform() == WINDOWS
+
+
+static func is_linux() -> bool:
+	return get_platform() == LINUX_BSD
+
+
+static func is_debug() -> bool:
+	return OS.is_debug_build()
+
+
+static func get_platform() -> int:
+	match OS.get_name():
+		"Windows", "UWP":
+			return WINDOWS
+		"macOS":
+			return MACOS
+		"Linux", "FreeBSD", "NetBSD", "OpenBSD", "BSD":
+			return LINUX_BSD
+		"Android":
+			return ANDROID
+		"iOS":
+			return IOS
+		"Web":
+			return WEB
+		_:
+			assert(false, "No such platform")
+			return -1