feat(keywords): add keywords command and it's linter

[jcs090218]

Add eask keywords to print all available keywords to used inside the ;; Keywords: ... header.

Example output for eask keywords:

Running Eask in the development environment
Press Ctrl+C to cancel.

Executing script inside Emacs...

  Checking Emacs version 29.0.50... done!
  Checking system windows-nt... done!
  Try constructing the package-descriptor (parse-it.el)... succeeded!
  Loading Eask file in c:/Users/JenChieh/Downloads/workspace/parse-it/Eask... done!

  abbrev       abbreviation handling, typing shortcuts, and macros
  bib          bibliography processors
  c            C and related programming languages
  calendar     calendar and time management tools
  comm         communications, networking, and remote file access
  convenience  convenience features for faster editing
  data         editing data (non-text) files
  docs         Emacs documentation facilities
  emulations   emulations of other editors
  extensions   Emacs Lisp language extensions
  faces        fonts and colors for text
  files        file editing and manipulation
  frames       Emacs frames and window systems
  games        games, jokes and amusements
  hardware     interfacing with system hardware
  help         Emacs help systems
  hypermedia   links between text or other media types
  i18n         internationalization and character-set support
  internal     code for Emacs internals, build process, defaults
  languages    specialized modes for editing programming languages
  lisp         Lisp support, including Emacs Lisp
  local        code local to your site
  maint        Emacs development tools and aids
  mail         email reading and posting
  matching     searching, matching, and sorting
  mouse        mouse support
  multimedia   images and sound
  news         USENET news reading and posting
  outlines     hierarchical outlining and note taking
  processes    processes, subshells, and compilation
  terminals    text terminals (ttys)
  tex          the TeX document formatter
  tools        programming tools
  unix         UNIX feature interfaces and emulators
  vc           version control
  wp           word processing

(Total of 36 keywords listed)

Example output for eask lint keywords:

Running Eask in the development environment
Press Ctrl+C to cancel.

Executing script inside Emacs...

  Checking Emacs version 29.0.50... done!
  Checking system windows-nt... done!
  Try constructing the package-descriptor (parse-it.el)... succeeded!
  Loading Eask file in c:/Users/JenChieh/Downloads/workspace/parse-it/Eask... done!


`parse-it.el` with keywords-lint
Missing a standard keyword, consider adding one to the Keywords header!

  Try the following command to see all available keywords,

    $ eask keywords