Do normalization on tag options
bug #9489 [DependencyInjection] Add normalization to tag options (WouterJ)

This PR was submitted for the 2.3-dev branch but it was merged into the 2.3 branch instead (closes #9489).

Discussion
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[DependencyInjection] Add normalization to tag options

Currently, when using tags in XML, the options aren't normalized. This means that the following code is wrong:

    <tag name="sonata_admin" manager-type="doctrine_phpcr" ... />

It should be `manager_name` to remove errors, but that's not following the XML rules. The solution is to use the same normalization as the configuration: replacing - with _.

To be BC, both options (with and without normalization) are kept

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Commits
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06d64d8 Do normalization on tag options