Various source optimizations, added MODX (CSM), updated links for InvoicePlane

README.md

@@ -195,6 +195,7 @@ CMS are a practical way to setup a website with many features. CMS often come wi
   * [ImpressPages CMS](https://www.impresspages.org/) - Easy code meets easy admin. ([Demo](https://www.impresspages.org/demo), [Source Code](https://github.com/impresspages/ImpressPages)) `GPLv3`/`MIT`  `PHP`
   * [Joomla!](http://www.joomla.fr/) - Advanced Content Management System (CMS) `GPL`
   * [KeystoneJS](http://keystonejs.com/) - Node.js CMS & Web Application Platform ([Demo](http://demo.keystonejs.com/), [Source Code](https://github.com/keystonejs/keystone)) `MIT` `Node.js`
+  * [MODX](http://modx.com/) - MODX is an advanced content management and publishing platform. The current version is called 'Revolution'. ([Source Code](https://github.com/modxcms/revolution)) `GPLv2` `PHP`
   * [Movable Type](https://movabletype.org/) - a powerful solution for the creation and management of web content.
   * [october](http://octobercms.com/) - Free, open-source, self-hosted CMS platform based on the Laravel PHP Framework. ([Source code](https://github.com/octobercms/october)) `MIT`
   * [Pagekit](http://pagekit.com/) - A new modern CMS to create and share ([Source code](https://github.com/pagekit/pagekit)) - `MIT`
@@ -312,7 +313,7 @@ CMS are a practical way to setup a website with many features. CMS often come wi
 
   * [GLPI](http://www.glpi-project.org/spip.php?lang=en) - GLPI is an IT assests/resources/inventory manager ([Source code](https://forge.glpi-project.org/projects/glpi)) `GPLv2` `PHP`
   * [GRR](http://grr.devome.com/?lang=en) - Assets management and booking for small/medium companies ([demo](http://grr.devome.com/demo/week_all.php?year=2015&month=07&day=28&area=94), _administrateur/azerty_) `GPLv2` `PHP`
-  * [InvoicePlane](https://invoiceplane.com/) - Manage quotes, invoices, payments and customers for your small business. - `MIT`
+  * [InvoicePlane](https://invoiceplane.com/) - Manage quotes, invoices, payments and customers for your small business. ([Demo](https://demo.invoiceplane.com), [Source code](https://github.com/InvoicePlane/InvoicePlane)) - `MIT`
 
 
 ## Monitoring and Administration
@@ -470,7 +471,8 @@ CMS are a practical way to setup a website with many features. CMS often come wi
 
 ## Static site generators
 
-See https://staticsitegenerators.net and https://www.staticgen.com
+See [staticsitegenerators.net](https://staticsitegenerators.net) and [staticgen.com](https://www.staticgen.com)
+
 
 ## URL Shorteners