Add network menu item to the main page of repository

github-network.user.js

// ==UserScript==
// @name github-network.user.js
// @namespace https://github.com/
// @description Add network menu item to the main page of repository
// @include https://github.com/*
// @version 2.0.1
// @grant none
// ==/UserScript==
var repo = window.location.pathname;
if (repo) {
    repo = repo.match(/(\/[^/]+){2}/)[0];
}
var $menu = $(".reponav");

if (!repo || !$menu[0]) {
    return;
}

var networkHtml = '<a data-selected-links="repo_graphs repo_contributors {{REPO}}/network" class="js-selected-navigation-item reponav-item" href="{{REPO}}/network">' +
    '<span class="octicon octicon-gist-fork"></span>' + 
    'Network' +
'</a>';

networkHtml = networkHtml.replace(/{{REPO}}/g, repo);

$menu.append(networkHtml);