feat(eslint-plugin): [space-infix-ops] support for class properties and type aliases

[FDIM]

Hey,

I've bumped into this issue after migrating to eslint. Nice work btw! We've used whitespace rule in tslint for certain formatting and this PR will bring feature parity closer to what was there before. I know it's about whitespace, but moving to prettier is just too much for our code base and the patterns we are used to. Maybe one day :) (plenty of things gets far less readable)

Fixes #1699

A bit later I'll also have a look at #1606

EDIT:
2nd commit fixes first part of #1606

[typescript-eslint]

Thanks for the PR, @FDIM!

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 #3231 (394922b) into master (d0d7186) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #3231      +/-   ##
==========================================
+ Coverage   92.90%   92.92%   +0.02%     
==========================================
  Files         316      316              
  Lines       10839    10848       +9     
  Branches     3064     3066       +2     
==========================================
+ Hits        10070    10081      +11     
+ Misses        343      342       -1     
+ Partials      426      425       -1     

Flag	Coverage Δ
unittest	92.92% <100.00%> (+0.02%)	⬆️

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

Impacted Files	Coverage Δ
...ackages/eslint-plugin/src/rules/space-infix-ops.ts	97.43% <100.00%> (+7.43%)	⬆️

[bradzacher]

LGTM - thanks for your contribution!