add limesurvey as a polling tool

README.md

@@ -260,6 +260,7 @@ CMS are a practical way to setup a website with many features. CMS often come wi
 
 ## Polls and events
 
+ * [LimeSurvey](https://www.limesurvey.org) - Feature-rich Open Source web based polling software. Supports extensive survey logic. - ([Demo](https://demo.limesurvey.org))
  * [OpenSondage](https://github.com/leblanc-simon/OpenSondage) - an online service for planning an appointment or make a decision quickly and easily: Make a poll, Define dates or subjects to choose, Send the poll link to your friends or colleagues, Discuss and make a decision - ([Demo](http://framadate.org/), [Example](https://framadate.org/aqg259dth55iuhwm))
  * [Kyélà](http://kyela.net/) -  Participation polls for group events  - ([Source code](https://github.com/abienvenu/Kyela), [Demo](http://kyela.net/55232734237c8/))
  * [MaterialPoll](https://github.com/nearbycoder/materialpoll) - an opensource strawpoll.me clone for creating random polls. - ([Source code](https://github.com/nearbycoder/materialpoll), [Demo](http://materialpoll.tk))
@@ -361,3 +362,4 @@ CMS are a practical way to setup a website with many features. CMS often come wi
   * [Wikimatrix](http://www.wikimatrix.org/) - A wiki platforms comparator
   * [WiKiss](http://wikiss.tuxfamily.org/) - un wiki simple à utiliser et déployer.
   * [Wikitten](https://github.com/victorstanciu/Wikitten) - Wikitten is a small, fast, PHP wiki, and the perfect place to store your notes, code snippets, ideas, and so on.
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