Make JSON serialization and deserialization dynamic

• Easier to add installation options in the future
• Deserializing only happens with JSON, YAML and XML will get translated to JSON prior to serialization
• Deserialization will happen dynamically, making it easier to add new fields to packages InstallationOptions.
• Bundle manifest updated to v3

NOTE: Newer (v3) XML bundles won't be compatible with older UniGetUI versions. v3 UBUNDLE, JSON and YAML bundles should work as expected with older UniGetUI releases