More lifecycle events/fixes

Signed-off-by: Chris Sanders <zidane@outlook.com>
README clarification

Signed-off-by: Chris Sanders <zidane@outlook.com>
added checkstyle plugin, cleaned up build.gradle
Say hi to Travis CI.
Update README.
Have Travis only build on Java 6.
Have Travis use the Gradle wrapper.
Compile with openjdk6 rather than oraclejdk6.
Don't use the Gradle wrapper after all.

Going to have to blame Abrar for that one.
Travis build status in README
fixed name set error
Fixed typo (brance -> brace)
Add basic PR guidelines
Added irc webclient URL
World/chunk interface

Adding core world/chunk interface.

*Note* `World` will need a way to return all loaded chunks,
but we'll need some discussion as to what containing object structure
should be used.
Add Block, javadoc cleanup

Add ignoresCancelled to SpongeEventHandler

Signed-off-by: Chris Sanders <zidane@outlook.com>
Add majority of the lifecycle events

@cpw feel free to remove any un-necessary for Sponge

Signed-off-by: Chris Sanders <zidane@outlook.com>
Add Item/ItemBlock

Signed-off-by: Chris Sanders <zidane@outlook.com>
Correct my faiure to follow conventions

Signed-off-by: Chris Sanders <zidane@outlook.com>
Added Licence to Item and ItemBlock