Fixed relative path.

Author: Martynas Žilinskas

example/dist/hello.js

@@ -1,2 +1,2 @@
 /* Generated by main-file-generator */
-module.exports.default = require('../build.js').Default;
+module.exports.default = require('build.js').Default;

example/dist/world.js

@@ -1,2 +1,2 @@
 /* Generated by main-file-generator */
-module.exports.default = require('../build.js').World;
+module.exports.default = require('build.js').World;

src/generator.ts

@@ -43,7 +43,10 @@ export default class Generator {
 
             // Get `require` relative path.
             let requireFileFullPath = path.join(process.cwd(), this.config.proxyjs.requireFile);
-            let requireFileRelativePath = path.relative(fullFilePath, requireFileFullPath).split(path.sep).join('/');
+            let requireFileRelativePath = path.relative(path.dirname(fullFilePath), requireFileFullPath);
+            if(path.sep !== "/") {
+                  requireFileRelativePath = requireFileRelativePath.split(path.sep).join('/');
+            }
 
             console.log(fullFilePath);
             //Write to file