feat: add ability to create cert interactively

[nothinux]

with this feature, user can create CA, intermediate CA and Certificate interactively using -interactive flag.

[codecov-commenter]

Codecov Report

Merging #10 (176e4c3) into master (925a2f8) will decrease coverage by 7.25%.
The diff coverage is 1.40%.

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@@            Coverage Diff             @@
##           master      #10      +/-   ##
==========================================
- Coverage   80.94%   73.69%   -7.25%     
==========================================
  Files           5        6       +1     
  Lines         698      768      +70     
==========================================
+ Hits          565      566       +1     
- Misses         94      162      +68     
- Partials       39       40       +1     

Impacted Files	Coverage Δ
cmd/certify/helper.go	85.71% <0.00%> (ø)
cmd/certify/interactive.go	0.00% <0.00%> (ø)
cmd/certify/main.go	59.03% <25.00%> (-1.73%)	⬇️