Mob Crawl

First public release.

• Hostile mobs lie down and crawl through one-block gaps, both at floor level and ceiling level
• Mobs crawl only when it actually helps them reach their target, and stand up once they are through
• Creepers can explode while crawling
• Model tilts forward while crawling; creeper and witch heads face forward
• No suffocation damage while squeezing through
• Whitelist and blacklist with modid:* wildcards, plus whitelistOnly mode for heavy modpacks
• Separate tiltBlacklist for mobs whose own animations conflict with the tilt
• /mobcrawl status command for diagnosing mob behaviour
• Spiders and cave spiders are excluded by default, they already fit through one-block gaps