[CIRCLE-12217] Create orb from CLI

[hannahhenderson]

Makes an orb. BOOM.

Also provides some handy information in help:

[codecov-io]

Codecov Report

Merging #31 into create-namespace will decrease coverage by 0.45%.
The diff coverage is 30%.

@@                 Coverage Diff                  @@
##           create-namespace      #31      +/-   ##
====================================================
- Coverage             42.23%   41.77%   -0.46%     
====================================================
  Files                    11       11              
  Lines                   715      742      +27     
====================================================
+ Hits                    302      310       +8     
- Misses                  390      409      +19     
  Partials                 23       23

Impacted Files	Coverage Δ
cmd/diagnostic.go	27.27% <0%> (ø)	⬆️
cmd/build.go	34.32% <0%> (ø)	⬆️
cmd/orb.go	30% <32.14%> (-0.05%)	⬇️

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