UserMailer() function revision to allow for parameters in the form "name (..)
Currently, the function UserMailer() does only allow to pass parameters of the
form "emailaddress" but not "name (..) <emailaddress>.
The reasons are i.a. a mal-function of the used php mail() function, when a
fully quoted-Printable string qp("name (..) <emailaddress>") is passed to php
mail() function, where it appears to work only with "qp("names (..)")
I propose and will change UserMailer() accordingly to fit both requirements, the
old form (address only) and the "name <emailaddress>" form by using the
wfQuotedPrintable() function for those partial strings which need this.
UserMailer can then be used as the one and only emailer (for Special:emailuser,
"I forgot my password" and of course, Enotif).