Remove @peer for modules that use HttpClient

The HttpClient mixin has a peer() method, therefore these modules
should not have to make their own. Also new module writers won't
repeat the same old code again.
I missed this one
Land #2718, @wchen-r7's deletion of @peer on HttpClient modules
Add Rex::Proto::PJL and PoC modules
Handle @wchen-r7's comments
Handle @jlee-r7's comments
Add filesystem commands and more PoC modules