stub for top-level corporations API call (separate from a character-level call, showing that pilot's history)
corporate membership history for individual pilots
include Corporation class
syntax fixes because i'm sloppy at everything
corporation_list attribute; used by at least Character class
need to actually stash away the corp list, as well as return it to the method caller
should probably use the correct API path
Maybe-ify a few attributes to allow value|undef
nodevalue or undef, since the member_limit isn't always part of the API's response (non-director characters or non-corporate keys)