feat(eslint-plugin): [naming-convention] add modifiers exported, global, and destructured

[bradzacher]

Fixes #2239
Fixes #2512
Fixes #2318
Closes #2802

Adds the following modifiers:

• exported - matches anything that is exported from the module.
• global - matches a variable/function declared in the top-level scope.
• destructured - matches a variable declared via an object destructuring pattern (const {x, z = 2})

[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 #2808 (c4cb9f2) into master (665b6d4) will decrease coverage by 0.06%.
The diff coverage is 82.08%.

@@            Coverage Diff             @@
##           master    #2808      +/-   ##
==========================================
- Coverage   92.78%   92.71%   -0.07%     
==========================================
  Files         301      301              
  Lines       10159    10191      +32     
  Branches     2870     2889      +19     
==========================================
+ Hits         9426     9449      +23     
  Misses        345      345              
- Partials      388      397       +9     

Flag	Coverage Δ
unittest	92.71% <82.08%> (-0.07%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...kages/eslint-plugin/src/rules/naming-convention.ts	88.43% <82.08%> (-1.39%)	⬇️