Fix issue #4470: allow numbers in vendor and class names

[nhp]

As there are many companies that use numbers in their name it would be good to allow those to use them in their classes and vendor names.

Description

To enable a widely used naming scheme, with numbers, the xsd files needed to be adapted else the names could not be validated

Fixed Issues (if relevant)

1. import.xml doesn't allow numbers in vendor name and class name #4470: import.xsd doesn't allow numbers in vendor name and class name

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[orlangur]

Any idea why we need underscore allowed?

[magento-cicd2]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 3 committers have signed the CLA.

✅ nhp
❌ paliarush
❌ viktym

[vkublytskyi]

@nhp thank you for this contribution.

Provided regex allows invalid value such as 1invalidClassName. As Model name potentially could be any valid PHP class name (FQCN to be precise) and according to PHP documentation full regexp should looks like:

(?:\\?[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*)+

[magento-engcom-team]

Hi @nhp
We are closing this Pull Request now due to inactivity. Additionally, some misplaced commits are present in changeset at the moment.

If you wish to proceed please create a new PR or reopen this one fixing up the history.

Thank you.