Partial extension host, some restructuring

I didn't like how the inner objects accessed parent objects, so I
restructured all that.

transformer.js

@@ -0,0 +1,27 @@
+// This file is included via a regular Node require. I'm not sure how (or if)
+// we can write this in Typescript and have it compile to non-AMD syntax.
+module.exports = (remoteAuthority) => {
+	return {
+		transformIncoming: (uri) => {
+			switch (uri.scheme) {
+				case "vscode-remote": return { scheme: "file", path: uri.path };
+				case "file ": return { scheme: "vscode-local", path: uri.path };
+				default: return uri;
+			}
+		},
+		transformOutgoing: (uri) => {
+			switch (uri.scheme) {
+				case "vscode-local": return { scheme: "file", path: uri.path };
+				case "file ": return { scheme: "vscode-remote", authority: remoteAuthority, path: uri.path };
+				default: return uri;
+			}
+		},
+		transformOutgoingScheme: (scheme) => {
+			switch (scheme) {
+				case "vscode-local": return "file";
+				case "file": return "vscode-remote";
+				default: return scheme;
+			}
+		},
+	};
+};