Fix relative path parsing on windows when using fastparquet (#4445)
Fix relative path parsing on windows when using fastparquet (#4445)

* Fix fastparque relative path parsing on Windows

* Fix path parsing when using fastparquet reader on Windows

jakirkham/dask,dask/dask,dask/dask,ContinuumIO/dask,jcrist/dask,blaze/dask,ContinuumIO/dask,jcrist/dask,jakirkham/dask,mrocklin/dask,blaze/dask,mrocklin/dask