Config File Simplification (#9)

* New: Config File Simplification

* Added missing key

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Fix  typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Incorporating first round of feedback

* Add Teddy's extends proposal

* Change files and ignore to arrays

* .eslint.config.js -> eslint.config.js

* Add --ext example, remove Config.create

* Added two more FAQs

* Update config array behavior

* Remove  class - no longer needed

* Clarify command line changes

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Update config name options

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Clarify files/ignores matching order

* Updated directory processing on command line

* Fix typo

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* ruledefs namespaces must be unique; plugins specifying namespaces

* Clarify what happens when 'eslint .' is run

* Clarify what a config function can return

* Clarify when 'files' is required in a config array

* Clarify what a config with no 'files' does

* Add note about node_modules

* Remove @eslint/config package

* Add 'name' key for configs

* Remove 'extends'

* Add section on shareable config names

* Add more info about shareable configs

* Clarify merging for same ruledefs namespace

* Add open question about running eslint alone

* Clarify shareable config file structure

* Cleanup shareable configs compat section

* Allow functions in config arrays

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Add missing period

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Add implementation details

* Remove --use-eslintrc typo

* Emit warnings when unnecessary options are ignored

* Clarify when error is thrown for dupe ruledefs

* should -> may

* Validate config when normalized

* Updated open questions

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* Fix typo

Co-Authored-By: nzakas <nicholas@nczconsulting.com>

* ruledefs -> defs.ruleNamespaces

* Add back @eslint/config, explain back compat features

* ruleNamespaces -> plugins

* Cleanup description of parsers and processors

* Update designs/2019-config-simplification/README.md

Co-Authored-By: Alex Zherdev <alex_zherdev@acl.com>

* defs.plugins -> plugins

* Update: languageOptions and environments

* Update: Grepping patterns

* New: languageOptions, node env compat, @eslint/config update

* Update: @eslint/eslintrc utility

* Update: Misc updates

* Update: Add reportUnusedDisableDirectives option

* Update: Clarifications and finishing touches

* Update: Add in plugin parsers support

* Update: Clarify plugin namespaces

* Update: Remove context#hasRule()

* Update: Mention features that were added after the RFC was written

* Add AND operator for files key

* Some cleanup

* Move linterOptions to top level of config

* Update ignore patterns details

* Specify option to Linter#verify() for disabling environments

* Rename ConfigArray -> ESLintConfigArray

* Remove default .gitignore

* Clarify behavior of files/ignores

* Add back in .eslintignore

* Update development plan

* Update designs/2019-config-simplification/README.md

Co-authored-by: Brandon Mills <btmills@users.noreply.github.com>

Co-authored-by: Kevin Partington <platinum.azure@kernelpanicstudios.com>
Co-authored-by: Brandon Mills <btmills@users.noreply.github.com>
Co-authored-by: Teddy Katz <teddy.katz@gmail.com>
Co-authored-by: Alex Zherdev <alex_zherdev@acl.com>

designs/2018-processors-improvements/README.md

@@ -6,6 +6,7 @@
 
 ## Summary
 
+
 This proposal provides a way to explicitly define which processor(s) to use for different files inside of configuration. It also allows the chaining of multiple processors to fully process a file.
 
 ## Motivation