Add blocking of entry to ELECTRIC and ENTRY regions to monsters

[skore87]

Found source code to add functionality to the ELECTRIC and ENTRY flags so it can also block monsters from entry.

Custom Entity:
https://github.com/betterphp/BloodMoon/blob/master/src/main/java/uk/co/jacekk/bukkit/bloodmoon/entities/BloodMoonEntityZombie.java

Entity Replacement:
https://github.com/betterphp/BloodMoon/blob/master/src/main/java/uk/co/jacekk/bukkit/bloodmoon/EntityReplaceListener.java

Entity type numbers:
https://github.com/Bukkit/mc-dev/blob/master/net/minecraft/server/EntityTypes.java#L94