Fix: add redirect for get involved page

Author: lwasser

_pages/redirects/community/get-involved-contact.md

@@ -0,0 +1,8 @@
+---
+title: Old Get involved page redirect
+permalink: get-involved-contact.html
+redirect_to: https://www.pyopensci.org/volunteer.html
+---
+
+Oops - looks like you're looking for our {{ page.title }}. Directing you
+to the right page now: <a href="{{ page.redirect_to }}"> {{ page.redirect_to }} </a>