Feature Request

Hi! I'm not sure whether to treat this as a bug or a feature request, so feel free to relabel it.

In a c_cpp_properties.json file, you can add a * to the end of a browse path (e.g. C:\\my\\source\\folder\\*) to specify that it should only look for files directly in that folder and not recursively index subfolders. This doesn't seem to work when providing a browse configuration from a custom configuration provider. Cpptools will complain that the path doesn't exist and ignore it:

 Unable to index files from non-existent folder: C:\my\source\folder\* 

In my case, the provider knows exactly which files are part of the project, and I want to limit which files cpptools indexes as much as possible to prevent it from finding potentially conflicting symbol definitions in unrelated files. Disabling the recursive lookup would help a lot (even better would be if a custom provider could provide a set of files to index instead of a set of directories).