Add HLS support

[0xA50C1A1]

Please sign (check) the below before submitting the Pull Request:

• I have signed the ntop Contributor License Agreement at https://github.com/ntop/legal/blob/main/individual-contributor-licence-agreement.md
• I have read the contributing guide lines at https://github.com/ntop/nDPI/blob/dev/CONTRIBUTING.md
• I have updated the documentation (in doc/) to reflect the changes made (if applicable)

Describe changes:

Nothing fancy, just a check against the HTTP Content-Type guaranteed to be used by that protocol.

[0xA50C1A1]

I'll update the unit test results a bit later.

[IvanNardi]

Thank you