update the author list; closes #6

.mailmap

@@ -4,3 +4,7 @@ Joana Fraxanet Morales <joana.fraxanet@gmail.com>
 Bowy La Riviere <b.m.lariviere@student.tudelft.nl>
 Lex Huismans <lexhuismans@outlook.com>
 Gian de Bruin <giandebruin@hotmail.com>
+Isidora Araya Day <isidora.araya@ug.uchile.cl>
+Kostas Vilkelis <kostasvilkelis@gmail.com>
+Hiresh Jadoenathmissier <hiresh_96@hotmail.com>
+Bowy La Rivière <bowylar1995@gmail.com>

AUTHORS.md

@@ -18,10 +18,18 @@ The following people contributed to making of these lecture notes:
 * Lars kleyn Winkel
 * Kostas Vilkelis
 * Joris van Winden
+* Isidora Araya Day
+* Brennan Undseth
+* Michael Borst
+* Umut Kalkan
+* Hiresh Jadoenathmissier
+* Bowy La Rivière
 
 <!--
 Execute
 git shortlog -s | sed -e "s/^ *[0-9\t ]*//"| xargs -i sh -c 'grep -q "{}" AUTHORS.md || echo "{}"'
 
 To check if any authors are missing from this list.
+
+Use git shortlog -se and add contributors to the .mailmap as necessary.
  -->