feat: add global flags

[RasPhilCo]

WIP

requires #94 #99

[codecov]

Codecov Report

Merging #101 (0b9c05c) into master (4b44270) will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master    #101   +/-   ##
======================================
  Coverage    0.00%   0.00%           
======================================
  Files           3       3           
  Lines          15      15           
  Branches        2       2           
======================================
  Misses         15      15           

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[RodEsp]

I believe this functionality has already been added with the addition of the --json global flag:

core/src/command.ts

Lines 115 to 120 in 11cbd6b

	private static globalFlags = {
	json: Flags.boolean({
	description: 'Format output as json.',
	helpGroup: 'GLOBAL',
	}),
	}

Do we still need this PR for anything or should we close it @RasPhilCo?