mod_blocklist: Drop blocked messages without error, option to restore compliant behavior
From XEP-0191:
> For message stanzas, the server SHOULD return an error, which SHOULD
> be <service-unavailable/>.
Following this may leak to a blocked JID that they have been blocked,
which seems contrary to the goal of pretending to be perpetually
offline.
syntax: glob
.hgignore
.luacheckcache
data
local
www_files
html/*
prosody.lua
prosody.cfg.lua
prosody.version
config.unix
*.patch
*.diff
*.orig
*.rej
*.save
*~
*.o
*.so
*.install
*.pid
*.log
*.err
*.debug
*.dll
*.exp
*.lib
*.obj
luacov.report.out
luacov.report.out.index
luacov.stats.out