Log::Any::Proxy does not pass @_

[dagolden]

(Issue details were lost during repo re-construction; this is a summary of
the conversation to the best of my recollection.)

• Gelu Lupaş opened an issue that Log::Any::Proxy logging functions only pass
  the first argument to the adapter.
• I replied that that behavior isn't documented and is inconsistent across
  adapters anyway
• After some back and forth (which identified other, unrelated bugs), I
  investigated existing adapter behavior. Some pass all arguments; some don't.
  Some underlying loggers vary as well: some concatenate with a space,
  others don't.
• I proposed that Log::Any::Proxy concatenate multiple arguments with
  a space for consistency.
• Gelu thought that was not the most flexible solution and was not inclined
  to maintain his adapter (Log::Any::Adapter::Handler) and I offer to take
  over maintenance