SAT Catalog for the mexican localization

This module installs a set of reference tables with the official values published by the Mexican tax authority (SAT). It does not add menus or buttons; the data is available to other modules of the Mexican localization that need to fill in electronic invoices (CFDI) and payroll.

The catalogs included cover: product/service codes with indicators for VAT and IEPS and border incentive, units of measure with symbol, postal codes with state and municipality, neighborhoods, payment forms, payment methods, cancellation reasons, CFDI usage, tax regimes, months, periodicity, relationship types, countries, and transport data (configuration, figure, part, subtype of trailer, permit type).

Each catalog stores a code and a description, and the display name is automatically shown as "[code] description" so users can search by either. Some catalogs add extra flags: tax regimes and CFDI usage indicate whether they apply to individuals or legal entities, and CFDI usage also lists applicable tax regimes. The country catalog can be matched to Odoo's standard country list by name.

All records are read-only for regular users, so the official values cannot be changed by mistake. A separate script (not part of the Odoo interface) can regenerate the data files from the SAT XLS file when the authority publishes updates.