Rework spamassassin functions:
Rework spamassassin functions:

1) now we support some plugins, so do not refuse to parse them
2) added freemail plugin
3) rework SA functions evaluation
4) add support for eval functions
5) add freemail eval

minaevmike/rspamd,minaevmike/rspamd,minaevmike/rspamd,andrejzverev/rspamd,amohanta/rspamd,dark-al/rspamd,AlexeySa/rspamd,andrejzverev/rspamd,andrejzverev/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,minaevmike/rspamd,AlexeySa/rspamd,awhitesong/rspamd,amohanta/rspamd,andrejzverev/rspamd,minaevmike/rspamd,AlexeySa/rspamd,minaevmike/rspamd,minaevmike/rspamd,awhitesong/rspamd,dark-al/rspamd,amohanta/rspamd,AlexeySa/rspamd,andrejzverev/rspamd,awhitesong/rspamd,AlexeySa/rspamd,dark-al/rspamd,minaevmike/rspamd,andrejzverev/rspamd,amohanta/rspamd,awhitesong/rspamd,dark-al/rspamd,amohanta/rspamd,minaevmike/rspamd,andrejzverev/rspamd,AlexeySa/rspamd,andrejzverev/rspamd,dark-al/rspamd