Fixed minor bug in CPAN::Mini::Inject::inject() if verbose.

[WolfgangPecho]

CPAN::Mini::Inject::inject() reports only the first module of a dist file if verbose is on. It should
report each injected Module for each dist file.

The line

 next if $already_injected{$file}++; 

prevented printing of other modules.

[simbabque]

Maybe the keys should be sorted? That would make reading the report easier. Since we cannot have them in the order they were done, we can at least have them in some order, rather than random.

[simbabque]

@wchristian I've reviewed this PR as part of my Pull Request Challenge entry for September 2017 and think it can be merged without problems. There's the one thing I think could be a bit more convenient, but that's trivial to add.

Updating the documentation might make sense too.

Passing a value to "inject" enables verbose mode, which lists each module as it's injected.

could become something like

Passing a value to "inject" enables verbose mode, which produces a report of all injected modules.

[briandfoy]

I've cherry-picked this into briandfoy/cpan-mini-inject@93b4e0d

[briandfoy]

This is part of 1.002. I can't close this issue though. Thanks,