Dates in ISO 8601 format are in line with what is used in nginx.org news,
and are generally less ambiguous and easier to work with.
The changes.xml was converted using sed:
$ sed 's/date="\(..\)\.\(..\)\.\(....\)"/date="\3-\2-\1"/g' changes.xml
Appropriate changes to changes.xsls were introduced.
- fixed "<br>" lookup (eliminates the need in " <br/>" hacks)
- fixed maximum length for unbreakable input
- fixed space lookup (allows a space at column 77 to break a line)
