please add CPAN::Reporter directory to cpan o conf [rt.cpan.org #66740]

[xdg]

https://rt.cpan.org/Ticket/Display.html?id=66740

It is very difficult to determine where a configuration file might be placed on
a MSWin32 system.
It would be nice if the .cpanreporter directory path were one of the config
options for the
cpan shell. That way one could find the directory and config files that are
being used.
This is an issue on systems with more than one perl install and associated file
trees
(e.g. Strawberry Perl Portable).

A related issue is the on my Strawberry Perl Portable install, the
.cpanreporter directory
was generated at C:/.cpanreporter rather than in the root of the strawberry
perl install.
I tried to trace to where things were decided but wasn't able to follow the
trail. Maybe
and explicit directory option could be used.