repl: use path.resolve() for the module.filename

Windows was seeing: "C:\\path\\to\\cwd/repl"

lib/repl.js

@@ -59,7 +59,7 @@ var context;
 exports.disableColors = process.env.NODE_DISABLE_COLORS ? true : false;
 
 // hack for require.resolve("./relative") to work properly.
-module.filename = process.cwd() + '/repl';
+module.filename = path.resolve('repl');
 
 // hack for repl require to work properly with node_modules folders
 module.paths = require('module')._nodeModulePaths(module.filename);