Regenerate ESN workaround

[CastagnaIT]

Check if this PR fulfills these requirements:

• My changes respect the Kodi add-on development rules
• I have read the CONTRIBUTING document.
• I made sure there wasn't another Pull Request opened for the same update/change
• I have successfully tested my changes locally

Types of changes

• New feature (non-breaking change which adds functionality)
• Feature change (non-breaking change which changes behaviour of an existing functionality)
• Improvement (non-breaking change which improves functionality)
• Bug fix (non-breaking change which fixes an issue)
• Breaking change (fix or feature that would cause existing functionality to change)
• Refactor (non-breaking performance or readability improvements)

Description

For unknow reasons after 24h any kind of ESN used is downgraded to 540p resolution,
the only working way for now is generate a new ESN every 24h 20h (EDIT: some reported that can happens also after about 22h).

This is a first attempt to fix #1509

This problem affect more in bad way Android devices,
users that have copied the full-lenght ESN of the original app will cause that original app will be downgraded to 540p for an unknown period of time.

This change will generate a new ESN automatically from its first run,
for Android devices will be generated a random full-lenght ESN by preserving the first part of the ESN (if previously customized)

In case of Feature change / Breaking change:

Describe the current behavior

Describe the new behavior

Screenshots (if appropriate):