feat(eslint-plugin): Support abstract members in member-ordering rule (#395)

[hsmitty93]

Fixes #395

Member-ordering rule before had no implementation for abstract members and were treating them as private. These changes support abstract members with 'abstract' being used as another scope.

Default order with abstract members is below the scopes 'static' and 'instance'

• Doc has been updated
• Tests passed including added Tests

[typescript-eslint]

Thanks for the PR, @hsmitty93!

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 #1004 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1004      +/-   ##
==========================================
+ Coverage   94.06%   94.06%   +<.01%     
==========================================
  Files         115      115              
  Lines        5086     5089       +3     
  Branches     1423     1426       +3     
==========================================
+ Hits         4784     4787       +3     
  Misses        174      174              
  Partials      128      128

Impacted Files	Coverage Δ
packages/eslint-plugin/src/util/misc.ts	88% <ø> (ø)	⬆️
...ackages/eslint-plugin/src/rules/member-ordering.ts	97.33% <100%> (+0.11%)	⬆️

[hsmitty93]

Will add more Unit tests to increase coverage

• Increase code coverage

[bradzacher]

LGTM, thanks for this!