Blender Git Loki

Merge remote-tracking branch 'origin/master' into temp-asset-browser-catalogs

Asset Catalogs: add catalog ID to AssetMetaData

Add field `char AssetMetaData::catalog_id[MAX_NAME]`, to hold the
catalog ID of the asset. This field should be set using the
`BKE_asset_metadata_catalog_id_set()` function, which ensures that there
are no spaces in the ID and that the field is not too long.

For now only used to show in the UI, for development/debugging purposes.

Asset Catalogs: test space in asset catalog path

Test for the support of spaces in asset catalog paths.

Cleanup: use same parameter name in declaration & definition

No functional changes

Cleanup: Asset Catalogs, use default constructors

Merge remote-tracking branch 'origin/master' into temp-asset-browser-catalogs

Asset Catalogs: first implementation of loading a catalog definition file

Asset Catalogs: rudimentary writing catalog definition files to disk

`AssetCatalogDefinitionFile::write_to_disk()` can be used to write asset
catalog definition files to a text file on disk. It is very rudamentary,
and should be improved by sorting the written catalogs.