Sync from libucl.
Optimize Hfilter
Merge pull request #35 from AlexeySa/patch-6

Hfilter: optimize hostname check
Merge pull request #34 from fatalbanana/master

Support HELO blacklist and fix options registration for RDNS blacklist
Allow override system predefined settings without touching .conf files
from distribution.
Merge pull request #36 from andrejzverev/master

Allow override system predefined settings without touching .conf files from distribution.
Fix issue with random numbers generator in dns.
Use more clever time values to setup entropy.
Fix with libucl.
Update ChangeLog for 0.6.8.
- Fix typo
Merge pull request #39 from andrejzverev/master

- Fix typo
Fix README.
Remove CC warning.
Remove deprecated code.

Reported by: Andrey Vohmyanin
Fix classifiers config for repeated sections.
Remove deprecated bitbucket homepage.
Increase default reject treshold.
Rename symbol in Hfilter

Rename symbol HFILTER_HOSTNAME_NOPTR to HFILTER_HOSTNAME_UNKNOWN
Rename symbol HFILTER_HOSTNAME_NOPTR