Version template for package docs

[jalvz]

Motivation/summary

The package spec contemplates a _dev folder, ignored by Fleet, for any arbitrary data.
We can use to contain the template for generating docs, so it is versioned and there are no clashes when once we have more than 1 package.

Checklist

I have considered changes for:

• documentation

[apmmachine]

💚 Build Succeeded

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Build stats

• Build Cause: Pull request #4568 updated

• Start Time: 2021-01-13T07:24:38.640+0000

• Duration: 42 min 25 sec

Test stats 🧪

Test	Results
Failed	0
Passed	4607
Skipped	124
Total	4731

Steps errors

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Run Window tests

• Took 9 min 20 sec . View more details on here

Compress

• Took 0 min 0 sec . View more details on here
• Description: tar --exclude=coverage-files.tgz -czf coverage-files.tgz coverage

Compress

• Took 0 min 0 sec . View more details on here
• Description: tar --exclude=system-tests-linux-files.tgz -czf system-tests-linux-files.tgz system-tests

[codecov-io]

Codecov Report

Merging #4568 (3db9827) into master (ad5d272) will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #4568      +/-   ##
==========================================
+ Coverage   75.88%   75.91%   +0.03%     
==========================================
  Files         161      161              
  Lines        9792     9792              
==========================================
+ Hits         7431     7434       +3     
+ Misses       2361     2358       -3     

Impacted Files	Coverage Δ
processor/otel/consumer.go	92.84% <0.00%> (-0.45%)	⬇️
kibana/connecting_client.go	70.17% <0.00%> (+8.77%)	⬆️