- MFH: Make iconv filter accept '.' as the delimiter between encoding names as

- MFH: Make iconv filter accept '.' as the delimiter between encoding names as
  well as '/'. It's impossible to specify the filter in php://filter without
  this fix.

# I hope this to be merged to 5.2 as well. This doesn't break BC as there is
# no such encoding name that contains '.'. (Andif there were to be such one,
# the filter is failed in the first place since it also uses '.' for the
# delimiter between the filter name and the "from" encoding name.