docs(eslint-plugin): cleanup: standardise extension doc style, mark deprecated rules

[bradzacher]

WTTS

• cleanup extension rule documentation so that they defer to the base rule docs where possible.
• mark deprecated rules as deprecated (Fixes Documentation for [ban-ts-ignore], [camelcase], [class-name-casing], [generic-type-naming], [interface-name-prefix], [member-naming], and [no-untyped-public-signature] are all unlinked #1854)
• fixes up a few places to use jsonc instead of cjson or json5.
  • cjson was never valid.
  • json5 is hard for people to copy+paste into their configs.

[typescript-eslint]

Thanks for the PR, @bradzacher!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

Thanks again!

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[codecov]

Codecov Report

Merging #1887 into master will not change coverage by %.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1887   +/-   ##
=======================================
  Coverage   94.48%   94.48%           
=======================================
  Files         162      162           
  Lines        7494     7494           
  Branches     2151     2151           
=======================================
  Hits         7081     7081           
  Misses        178      178           
  Partials      235      235           

Flag	Coverage Δ
#unittest	94.48% <ø> (ø)

Impacted Files	Coverage Δ
packages/eslint-plugin/src/rules/ban-ts-ignore.ts	100.00% <ø> (ø)