readme adapted to latest v4.0

readme adapted

Author: dpscience

README.md

@@ -1,4 +1,4 @@
-# DQuickLTFit  <img src="https://github.com/dpscience/DQuickLTFit/blob/master/Images/IconPNGRounded.png" width="25" height="25">   
+# DQuickLTFit  <img src="https://github.com/dpscience/DQuickLTFit/blob/master/Images/IconPNGRounded.png" width="25" height="25">   
 
 Copyright (c) 2016-2018 Danny Petschke (danny.petschke@uni-wuerzburg.de) All rights reserved.<br><br>
 <b>DQuickLTFit</b> - A Least-Square Fitting Tool for the Analysis of Positron-Lifetime Spectra consisting of discrete specific Lifetimes using the Levenberg-Marquardt Algorithm<br>
@@ -13,6 +13,9 @@ You can cite all versions by using the <b>DOI 10.5281/zenodo.1168285</b>. This D
 
 [![DOI](https://zenodo.org/badge/DOI/10.5281/zenodo.1168285.svg)](https://doi.org/10.5281/zenodo.1168285)
 
+## v4.x
+DQuickLTFit v4.0:<br>[![DOI](https://zenodo.org/badge/DOI/10.5281/zenodo.1414142.svg)](https://doi.org/10.5281/zenodo.1414142)<br>
+
 ## v3.x
 DQuickLTFit v3.02:<br>[![DOI](https://zenodo.org/badge/DOI/10.5281/zenodo.1219482.svg)](https://doi.org/10.5281/zenodo.1219482)<br>
 DQuickLTFit v3.01:<br>[![DOI](https://zenodo.org/badge/DOI/10.5281/zenodo.1208613.svg)](https://doi.org/10.5281/zenodo.1208613)<br>
@@ -55,4 +58,3 @@ For more details see [GNU General Public License v3](https://www.gnu.org/license
 
 
 
-