Add --ensure-newline-before-comments argument

[StephenBrown2]

Also adds config option from #1000 to the argument list.

Feel free to disregard, if the args list is getting too out of hand.

[codecov-io]

Codecov Report

Merging #1101 into develop will increase coverage by 0.08%.
The diff coverage is 100%.

@@             Coverage Diff             @@
##           develop    #1101      +/-   ##
===========================================
+ Coverage    84.63%   84.72%   +0.08%     
===========================================
  Files           42       42              
  Lines         3652     3653       +1     
  Branches       655      655              
===========================================
+ Hits          3091     3095       +4     
+ Misses         423      422       -1     
+ Partials       138      136       -2

Impacted Files	Coverage Δ
isort/main.py	72.38% <100%> (+0.13%)	⬆️
isort/wrap_modes.py	93.63% <0%> (+2.72%)	⬆️

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[timothycrosley]

This is great! Happy to have the args a little longer to keep things in sync.

Thanks!

~Timothy