Update maintainer list

[skip ci]

libs/maintainers.txt

@@ -76,6 +76,7 @@ intrusive             Ion Gaztanaga <igaztanaga -at- gmail.com>
 io                    Glen Fernandes <glenjofe -at- gmail.com>
 iostreams             Jonathan Turkanis <turkanis -at- coderage.com>
 iterator              David Abrahams <dave -at- boost-consulting.com>, Thomas Witt <witt - at - acm.org>, Jeffrey Lee Hellrung Jr. <jeffrey.hellrung -at- gmail.com>
+iterator_facade       Zach Laine <whatwasthataddress -at- gmail.com>
 lambda                Jaakko Jarvi <jarvi -at- cs.tamu.edu>
 lexical_cast          Antony Polukhin <antoshkka -at- gmail.com>
 local_function        Lorenzo Caminiti <lorcaminiti -at- gmail.com>