suffix PACKAGE-LOCALLY-NICKNAMED-BY with -LIST

  Less confusing, and more in line with PACKAGED-NICKNAMED-BY-LIST &co.

  (Thanks to Rudi Schlatte for heads-up.)
prohibit adding name of a package to itself as a local nickname

  Seems useless, confusing, and probably unintentional. Make it a
  continuable error, though. Thanks to Rudi Schlatte for thinking
  about this.

  So, NO MORE:

   (in-package :foo)
   (add-package-local-nickname :foo :bar)
   'foo::x ; => BAR::X