add NumFOCUS sponsored project and donation links

- added sponsored project link under NumFOCUS badge 
- added donation link and button from MDAnalysis/mdanalysis#2506

about.md

@@ -67,13 +67,15 @@ MDAnalysis is a fiscally sponsored project of NumFOCUS,
 a nonprofit dedicated to supporting the open source 
 scientific computing community. If you like MDAnalysis
 and want to support our mission, please consider making
-a donation to support our efforts. NumFOCUS is 501(c)(3)
+a [donation](https://numfocus.salsalabs.org/supportmdanalysis) to support our efforts. NumFOCUS is 501(c)(3)
 non-profit charity in the United States; as such, 
 donations to NumFOCUS are tax-deductible as allowed by law.
 As with any donation, you should consult with your 
 personal tax adviser or the IRS about your particular 
 tax situation.
 
+<a href="https://numfocus.salsalabs.org/supportmdanalysis" target="_blank" style="background:#FFA500;padding:10px;margin:10px 0px;text-align:center;text-decoration:none;font-size:12pt;color:#222222;font-family:Arial, Helvetica, sans-serif;display:inline-block;">Donate Now!</a>
+
 Through [NumFOCUS](https://www.numfocus.org) (and previously the [Python Software
 Foundation](https://www.python.org/psf/)) we have been participating in [Google
 Summer of Code](https://summerofcode.withgoogle.com/) since 2016. 
@@ -84,7 +86,7 @@ Foundation](https://www.nsf.gov/) and [NumFOCUS](https://www.numfocus.org).
 
 
 
-<a href="https://numfocus.org/">
+<a href="https://numfocus.org/project/mdanalysis">
 <img src="{{site.images}}/numfocus-sponsored.png" title="NumFOCUS sponsored project"
 	alt="NumFOCUS Sponsored" style="display: inline; float: left; height: 4em;" />
 </a>