Renamed define-internal-hook-activation in src/macros.lisp
* src/macros.lisp (define-internal-hook-activation): renamed
  define-per-instance-activated-hook ->
  define-internal-hook-activation; use `define-hook-activation' 
* src/package.lisp (package hooks): renamed exported symbol
  define-per-instance-activated-hook ->
  define-internal-hook-activation