This function creates a ReaddirThread object to read the directory in
a secondary thread. This will let us poll for results without hanging the
UI in the case where a music library is on very slow storage (such as
NFS).
The ReaddirThread will accumulate a list of files that can be polled
using the poll_result() function, which will return the files found since
the last call to poll_result().
Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>
Anna Schumaker
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