Improve InventoryCloseEvent handling. Fixes BUKKIT-3286

Currently there are several cases where a player will have their inventory
screen closed client side but we will not call an event. To correct this
we call the event when the server is the cause of the inventory closing
instead of just when the client is the cause. We also ensure the server is
closing the inventory reliably so we get the events. Additionally this
commit also calls the event when a player disconnects which will handle
kicks, quits, and server shutdown.
Fix animal spawning ignoring limits. Fixes BUKKIT-4180

Minecraft 1.5.2 changed mob spawning by ignoring persistent mobs from the
mob count. In CraftBukkit all mobs that previously used a separate hard
coded persistence system were ported to instead use this one. This causes
all animals to be persistent by default and thus never be counted. To
correct this issue we consider if the mob would be considered persistent
in the hard coded system as well when deciding if a mob should count.
Fix typo/logic error in previous commit
Send block updates even when applyPhysics is false.  Fixes BUKKIT-3971
The CraftBlock class is setting bit 0x4 of the update flag when bit 0x2
should in fact be set here. Bit 0x2 means "do updates"; bit 0x4 means
"don't do updates if the world is static, even when bit 0x2 is set".
Correct event handling for dispensing filled buckets. Fixes BUKKIT-4046

We only go through event creation and calling when dispensing filled buckets
if the bucket is able to place its liquid. However, the check for this is
incorrect so the event is not called when a block liquids can destroy is
in front of the dispenser. This commit fixes the check to match the checks
vanilla does when actually using the bucket.
Pass correct block when dispensing empty buckets. Fixes BUKKIT-3668
Updated version to 1.5.2-R0.1 in pom.xml for BETA.
Updated version to 1.5.2-R0.2-SNAPSHOT for development towards next release.
Update events for new inventory features in 1.5

This commit brings the InventoryClickEvent in line with the new Minecraft
changes in 1.5.

InventoryDragEvent (thanks to @YLivay for his PR) is added to represent the
new "dragging" or "painting" functionality, where if you hold an itemstack and
click-drag over several slots, the items will be split evenly (left click) or
1 each (right click).

The ClickType enum is used to represent what the client did to trigger the
event.

The InventoryAction enum is reserved for future expansion, but will be used to
indicate the approximate result of the action.

Additionally, handling of creative inventory editing is improved with the new
InventoryCreativeEvent, and handling of numberkey presses is also improved
within InventoryClickEvent and CraftItemEvent.

Also, cancelling a creative click now displays properly on the client.

Fixes BUKKIT-3692, BUKKIT-4035, BUKKIT-3859 (new 1.5 events), and fixes
BUKKIT-2659, BUKKIT-3043, BUKKIT-1479, BUKKIT-1450, BUKKIT-2659
BUKKIT-2897 (creative click events).