[Bug-gsl] Bad e-mail address in source files cquad.[cm]

[Pedro Gonnet]

Hi all,

I'm the original author of the gsl/integration/cquad.[cm] files. I recently
noticed that these still points to my old e-mail address
address@hidden, which has been dead for years now.

Could somebody please update this to my current (and hopefully more stable)
e-mail address address@hidden and append it to my name in the
copyright notice in files' headers?

Many thanks,
Pedro