Log Message:
p5-BackupPC-XS: update to 0.62

0.62
  force rewrite of attr file if xattr key fixup was applied
  fixed attrib refCnt when attrib is unchanged
  bpc_attrib_dirWrite() doesn't create empty attrib files

0.61
  fix view of migrated v3 backup
  convert_hv2file() ensures xattr type is hash, and uses correct keyLen+1
  added BackupPC::XS::FileDigest::digest and bpc_fileDigest()

0.60
  allow mtime to be signed in attrib files
  added bpc_attrib_fileIterate() and BackupPC::XS::Attrib::iterate()
  added checks that xattr key is 0x0 terminated
  increased some buffer sizes to avoid benign compiler warnings for snprintf()
  bpc_attribCache_loadPath() removes any extraneous BPC_FTYPE_DELETED file types
  bpc_attrib_buf2fileFull() calls bpc_attrib_xattrDeleteAll(file)