Release 1.5.2

Release 1.5.2

* [Conf] Add default config for spamassasssin plugin
* [Conf] Add default configuration for antivirus module
* [Conf] Add dkim signing docs
* [Conf] Add mx_check default config
* [Conf] Add replies config
* [Conf] Add trie default config
* [Feature] Add heuristic to find text parts in files
* [Feature] Add rule to detect broken content type
* [Feature] Allow to extract CTE in Lua API
* [Feature] Allow to set from address for a lua_task
* [Feature] Allow to set recipients of a task from Lua
* [Feature] Enchance text_part:get_content method
* [Feature] Remove + aliases from emails
* [Feature] Support rmilter block and dkim signature in CGP helper
* [Feature] Support running event loop from Lua
* [Fix] Antivirus: use scanner-specific redis prefix
* [Fix] Couple of fixes for DKIM signing module
* [Fix] Distinguish missing and broken mandatory headers
* [Fix] Do more heuristical detection for missing CTE
* [Fix] Do not resort cache on each check
* [Fix] Fix CGP escaping
* [Fix] Fix MISSING_MIME_VERSION rule for plain messages
* [Fix] Fix parsing of cte in expressions
* [Fix] Fix partial matches in rspamadm grep
* [Fix] Fix setting class on style field
* [WebUI] Auto-switch Throughput units to `msg/min` for very low rate
* [WebUI] Update D3Evolution to 0.0.2

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