Add minimum contribution requirements.

layouts/partials/contribute.html

@@ -31,7 +31,8 @@
                     Do you want to take part of our Call for Contributors campaign?<br>
                     Download the following document, compile it (all fields are optional)<br>
                     and email it to us.<br>
-                    You will join our pool of experts and wannabe developers and we will contact you with further instructions as soon as possible.<br><br>
+                    You will join our pool of experts and wannabe developers and we will contact you with further instructions as soon as possible.<br>
+                    A very good knowledge of English is required, along with knowing how to use git properly. <br><br>
                     <strong>1. <a href="https://cloud.parrotsec.org/s/JwmQtbYgjW2QLPi" target="_blank">Download the document</a></strong><br>
                     <strong>2. Read the Privacy Policy</strong><br>
                     <strong>3. Compile it</strong><br>