Add a convenience option to mkfiles.pl for Unix users. If you run

Add a convenience option to mkfiles.pl for Unix users. If you run
'mkfiles.pl -u', it will do its normal processing, then run mkauto.sh
to regenerate configure and Makefile.in, then run configure in the
Unix subdirectory to regenerate unix/Makefile. So it's a handy
one-stop shop for going all the way from a modified Recipe to the
end-product Unix makefile, if you're adding source files during
development.

git-svn-id: svn://svn.tartarus.org/sgt/putty@9242 cda61777-01e9-0310-a592-d414129be87e