Allow searching through historic 06perms.txt changes

[sjn]

Hei!

A few weeks ago, I needed to figure out when a CPAN module got it's ADOPTME co-maint removed. I had to use git grep to search through the PAUSE-git commit log. This was painfully slow, taking several hours in one case.

Would this be something cpan-meta-browser can help making easier? :-)

[sjn]

In the same breath, it would be awesome to also see historic ownership changes of a given module. This can be very useful in situations when it's necessary to figure out the background of security incidents, for example.