Update maintainer list

[skip ci]

libs/maintainers.txt

@@ -73,7 +73,7 @@ icl                   Joachim Faulhaber <afojgo -at- gmail.com>
 integer               Daryle Walker <darylew -at- hotmail.com>, Andrey Semashev <andrey.semashev -at- gmail.com>
 interprocess          Ion Gaztanaga <igaztanaga -at- gmail.com>
 intrusive             Ion Gaztanaga <igaztanaga -at- gmail.com>
-io                    Daryle Walker <darylew -at- hotmail.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>
 lambda                Jaakko Jarvi <jarvi -at- cs.tamu.edu>