Jeremiah and Jaakko are maintainers of enable_if

[SVN r31301]

libs/maintainers.txt

@@ -56,6 +56,7 @@ tuple                 Jaakko Jarvi <jarvi -at- cs.tamu.edu>
 type_traits           John Maddock <john -at- johnmaddock.co.uk>, David Abrahams <dave -at- boost-consulting.com>
 typeof                Arkadiy Vertleyb <vertleyb -at- hotmail.com>, Peder Holt <peder.holt -at- gmail.com>
 utility
+utility/enable_if     Jaakko Jarvi <jarvi -at- cs.tamu.edu>, Jeremiah Willcock <jewillco -at- osl.iu.edu>
 variant               Eric Friedman <ericbrandon -at- gmail.com>
 wave                  Hartmut Kaiser <hartmut.kaiser -at- gmail.com>
 xpressive             Eric Niebler <eric -at- boost-consulting.com>