Removed unused imports. Added some Javadoc.
Updated components added in the EntityFactory
Reverted some commenting changes
Small adjustment viewport centering
Added World.deleteLater method.

This partially fixes the ConcurrentModificationException bug, when used
appropriately.
Merge conflicts resolved.
Appendices added.
fixed bug where client instead of water was deletedduring evaporate
Fixed issue with Indexers.

Some Indexers where added multiple times, and the World did not
check for this. Now, it's possible to add only one Indexer of
each Class to the World.

This should also have solved the ConcurrentModificationException,
which occurred because of problems with such duplicate Indexers.
Added JavaDoc to RandomNoise class.
Fixed Con.Mod.Exception (again).

Added a few more safeguards. Please ensure from now on that
asserts are not used to check Entity.has(...), since this
commit invalidates that assumption. Use an if-statement instead.
Fixed persistent trees in client

Also the delete method used in the fire processor is now correct with
Patrick's previous fix.
Water creation adjustment

Removed useless make water function and added a solid component to the
water.
merge with master
added some fixes for water proccessor and water class