Fix JavaDoc. Fixes Bukkit-3198

- Fix JavaDoc for ConfiguraitonSection. Bukkit-3198
- Fix merge on Inventory.java
- Add missed JavaDoc from itemmeta improvement
Correcting typo in Javadoc. Fixes BUKKIT-3200
Fixed Javadoc typo. Fixes BUKKIT-3201
Fix the fix for Bukkit-3201

oh plurality
Change wording for FIREBALL. Fixes BUKKIT-3417
Set -> Get