Solves #90 - Database automatic upgrade

Solves #90 (closed)

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Add a way to automatically create a database in alpha mode, and upgrade it to the one currently use scheme version of the running of lektord, version mk-7.2 for now.

Done here

• Add the upgrade_db_scheme function
• Place it in the reg
• Implement the upgrade_db_scheme function
• When the upgrade_db_scheme is placed in the launched hook, it will force the db scheme update from the alpha version