Do not ignore &suffixes by default, but &wildignore

The Vim help for 'suffixes' says:
> Files with these suffixes get a lower priority when multiple files
> match a wildcard.

They shouldn't be ignored, e.g. '.h' is included in there by default:

> .bak,~,.o,.h,.info,.swp,.obj

The default for 'wildignore' is empty.

This adds some of the old defaults:

> ~, .o, .swp and .obj (anchored at the end)
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