Make all rule identifiers text based

[ssbarnea]

As we v5 is already a major version, we also take the opportunity to replace all numeric rule ids with text one, like pylint has.

The main reason for this is that the numeric ones were cryptic, while the new ones should be self-documented, at least for most cases.

While this rule changes the output due to new codes being printed it is backwards compatible as old codes are recognized, so users are not forced to update their skip lists when they upgrade. This should ease upgrades.

Checklist

• gather feedback from users regarding proposed new ids
• verify that generated documentation (RTD job output on github) for rules and command line listing via -L produce better results than in the past
• review listing of tags (categories) -T and assure that we do not have incorrect, redundant or confusing entries
• add aliases for old id to new ones and print warning, to allow people to migrate without forcing them to it right away
• add a safety check to enforce use of lowercase-with-dashes for rule ids, so we assure they remain consistent.

Example output of new rule IDs, do you find one that does not make sense? or that can better rephrased? Keep in mind that these IDs must be under ~30ch, and that they are followed by their shortdesc in most cases.:

# ansible-liunt -T
# List of tags and rules they cover
command-shell:  # Specific to use of command and shell modules
  - command-instead-of-module
  - command-instead-of-shell
  - deprecated-command-syntax
  - inline-env-var
  - no-changed-when
  - risky-shell-pipe
core:  # Related to internal implementation of the linter
  - internal-error
  - load-failure
  - parser-error
  - syntax-check
deprecations:  # Indicate use of features that are removed from Ansible
  - deprecated-bare-vars
  - deprecated-command-syntax
  - deprecated-local-action
  - deprecated-module
  - no-jinja-when
  - role-name
experimental:  # Newly introduced rules, by default triggering only warnings
  - risky-file-permisions
formatting:  # Related to code-style
  - no-jinja-nesting
  - no-tabs
  - playbook-extension
  - risky-octal
  - var-spacing
  - yaml
idempotency:  # Possible indication that consequent runs would produce different results
  - git-latest
  - hg-latest
  - no-changed-when
  - package-latest
idiom:  # Anti-pattern detected, likely to cause undesired behavior
  - command-instead-of-module
  - command-instead-of-shell
  - empty-string-compare
  - inline-env-var
  - literal-compare
  - missing-import
  - no-handler
  - no-loop-var-prefix
  - no-relative-paths
  - unamed-task
metadata:  # Invalid metadata, likely related to galaxy, collections or roles
  - meta-incorrect
  - meta-no-info
  - meta-no-tags
  - meta-video-links
unpredictability:
  - partial-become
  - risky-file-permisions
yaml:  # External linter which will also produce its own rule codes.
  - yaml

[samccann]

just a few misspellings...