Add an ABM function which resets heat to 0, since gates/controllers won't be cooled normally if they are moved (piston, etc...) during the cooling delay.
Merge pull request #106 from Novatux/heat

Add an ABM function which resets heat to 0, ...
Change mesecons signals so that they update effectors only after a globalstep, configurable to be on/off
Fix README a little and add piston sounds by suzenako, contributed by jordan4ibanez.
Fix bug where functions in Luacontroller EEPROM crashes the server (fixes #107).
Support cyclic references in luacontroller memory tables, prohibit usage of goto statement (bugs reported by Nore).
mesecon:rules_link nil return rule
Fixes https://github.com/Jeija/minetest-mod-mesecons/issues/108
Merge remote-tracking branch 'refs/remotes/origin/master'