Release 0.7.2.

Release 0.7.2.

* Convert all maps to the compressed radix trie
* Allow IPv6 addresses in IP maps
* Remove dynamic items support from symbols cache
* Allow hex encoded output of strings
* Fix bug with control connections count
* Process fuzzy weight correctly (reported by @fatalbanana)
* Remove extra reference retain of http connection on error
* Remove deprecated options from the default config
* Add `one_shot` attr to metric's symbols
* Doc: add documentation for metrics
* Add Upstart job to debian packaging (by @CameronNemo)
* Config: improve SURBL symbols descriptions (by @citrin)
* Config: reflect SURBL changes (by @citrin):
    - Outblaze removed, malware moved to separate list:
	http://www.surbl.org/news/internal/MW-malware-sublist-added-to-multi
* Fix C modules initialization on restart
* Treat single IP as a single IP in radix lists (reported by @citrin)
* Do not touch file and core limits if not asked explicitly (reported by @citrin)
* Improve logging for fuzzy errors
* Block SIGPIPE for HTTP writing
* Doc: update manual pages
* Fix HTTP connection termination
* Reduce default number of parallel requests to 8
* Sync with libucl include features

Signed-off-by: Vsevolod Stakhov <vsevolod@highsecure.ru>