With a blank @author, makeinfo complains.
Without @author at all, the title page in TeX output looks funny.
So this commit simply names the authors, as determined by "git log" on
the doc/dev directory.
@title PSPP Developers Guide
@subtitle GNU PSPP Statistical Analysis Software
@subtitle Release @value{VERSION}
@title PSPP Developers Guide
@subtitle GNU PSPP Statistical Analysis Software
@subtitle Release @value{VERSION}
+@author Ben Pfaff
+@author John Darrington
@page
@vskip 0pt plus 1filll
@insertcopying
@page
@vskip 0pt plus 1filll
@insertcopying