Add getAPIVersion and getImplementationVersion

Signed-off-by: Steven Downer <grinch@outlook.com>
Merge pull request #12 from Grinch/master

Add getAPIVersion and getImplementationVersion
Add Entity/Player interfaces

First steps in entity/player interfaces - returning the UUID for all, and last
known name/display name for the Player.

`Entity` -> `LivingEntity` -> `HumanEntity` -> `Player`
Update README PR guidelines

Based on feedback so far
World/Chunk load/unload events

Adds abstract classes for `World`/`Chunk` load and unload events.
Adding BlockEvent abstract class

Adding a base `BlockEvent` interface.
Merge pull request #5 from prism/interface-entity

Add entity/Player interfaces
Add Contribution Guidlines link to README
Merge pull request #20 from prism/events-world

World/Chunk load/unload events
Merge pull request #34 from prism/events-block

Adding BlockEvent abstract class
Merge pull request #39 from simon816/readme-guideline-link

Add Contribution Guidlines link to README
Added a system for creating chat messages with a style.
Supports colors, fancy stylings, and click/hover events.
Merge branch 'master' of git://github.com/SpongePowered/SpongeAPI into chat

Conflicts:
	src/main/java/org/spongepowered/api/Game.java