Many crashes are caused by outdated or corrupted XNB files. Add logic to parse and validate all XNB files during startup and after a SMAPI mod edits the data.

Potential things to validate:

• data type (e.g. accidentally replacing a data XNB with a texture XNB);
• data format (e.g. number and format of fields);
• map issues.

The scope for this task is too broad; smaller tickets will be created as needed instead.