* Fix Mail::Rspamd::Client

  things TODO:
  - improve interaction with rspamc
  - improve documentation
  - test all features
  - test clustering
  - write CGI front-end

* Add ability to specify multiplier when learning
* Add statistics about spam and ham messages

* Add support for spf 2.0 (Sender ID policy)
* Add support of MAP_NOCORE to systems that supports it (FreeBSD for example)

  - each username is passed throught metaphone filter
  - then we make prefix tree based on english letters from metaphone
  - then we are searching for the longest common string and output result (how many times we got that string)

* Some additions to radix tree library:
  - allow tree traverse
  - add new insert methods (add and replace)
  - store keys in radix nodes (thought we can calculate key by bits, but I think that storing key is not too expensive)
  - values in a tree are now uintptr_t

* Add messages from spf checks

* Update help message for rspamc

* Add local_scan.c from Anton Nekhoroshikh for exim MTA

  - custom filters are dlopened and provides callbacks for user's input processing
  - custom filters can be used to extend rspamd functionality for unusual (non email processing cases)
  - custom filters allows to use rspamd async IO model and process management for performing custom network tasks

  - now it is possible to specify files and directories in arguments to rspamc
  - EXPERIMENTAL support of IMAP fetching including SSL support

  - independent and customizeable buffering
  - line buffering
  - errors handling support
  - custom (ip based) debug
  - append function name automaticaly (based on __FUNCTION__)
  - add some logic to logs system

* Do not use flock directly in pidfile handling

* Fix dependency on lex and yacc sources

TODO:
  - add properties to get all parameters of input task
  - add properties to statfile object
  - add some normalization function for calling from classify process
  - document changes

* Remove LRU expiration logic from statfiles and replace it with random/lowerest value expiration logic:
  expire random block or block with lowerest value

! statfiles are incompatible again

  - for Mail::Rspamd::Client
  - for HTTP redirector
  - for SPF module
  - for fuzzy storage
  - for statfile synchronization

  - add macros support
  - fix include command
  - fix exists command
  - add handling of DNS errors
  - fix all records in include parts
  - fix some issues with ip masks

  - add plugin to work with spf records (initial version)
  - make all spf types working (except include and redirect that still need some attention)
  - add support of MX records to evdns
  - some major fixes and testing of the whole spf subsystem

  - fix bug with mmapping files: new addresses must NOT be allocated in shared memory by themselves
  - fix bug with winnow classifier that totally brokes it down
  - fix bug with too much grow of values
* Use double precission values in statistics
* Add statistics for statfiles
* Add more informative data to output of LEARN command (weight of incoming message)
* Add weight to output of classifier as well