Set version to 0.5.1 due to massive lua changes.
Set version to 0.5.1 due to massive lua changes.

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