[Validator] Added ISBN validator
merged branch thewholelifetolearn/master (PR #6718)

This PR was squashed before being merged into the master branch (closes #6718).

Discussion
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[Validator] Added ISBN validator

Bug fix: no
Feature addition: yes
Backwards compatibility break: no
License of the code: MIT

For information about ISBN-10 and ISBN13: https://en.wikipedia.org/wiki/Isbn

This constraint permits to valid a ISBN-10 code, a ISBN-13 code or both on a value

Commits
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4582261 [Validator] Added ISBN validator
[Validator] fixed CS