util.openssl: Remove Lua 5.1 os.execute() return value compat

util.human.io: Fix handling of os.execute() return values in Lua 5.2+ Wrong part of Lua 5.1 compat removed in 0f4feaf9ca64

util.mathcompat: Module to ease reuse of math.type() Mostly to ensure it is available during tests, as util.startup is not invoked there

util.startup: Provide a common Lua 5.3+ math.type() for Lua 5.2 Code deduplication

Merge 0.12->trunk

util.startup: Ensure import() is available in prosodyctl (thanks keyzer) Fixes error in mod_authz_internal due to import() being unavailable as it was only loaded in Prosody proper

util.smqueue: Improve tests Result of mutation testing. One mutant remaining.

util.jsonpointer: Improve tests Result of mutation testing Remaining mutants are mostly relating to the math.type() fallback. Another case being that array[#array+1] == array[#array+2] and thus doesn't matter.

util.datamapper: Remove leftover debug assert (Only Teal, not included in build)

mod_blocklist: Add option 'migrate_legacy_blocking' to disable migration from mod_privacy Tiny performance improvement for new users by skipping this check. Most servers should have gone trough the migration for all active users long ago. As a suitable first step of phasing out this code, we make it possible to disable it first. Later it can be disabled by default, before finally the code is deleted.