correctly handle non-seekable filelikes passed into setcontents
correctly handle non-seekable filelikes passed into setcontents

piranna/pyfilesystem,pmitros/pyfs,Konubinix/pyfilesystem,pombreda/pyfilesystem,PyFilesystem/pyfilesystem,rivenz/pyfilesystem,flying-circus/pyfilesystem,pmitros/pyfs,zopyx/pyfilesystem