Added messages, renamed cake_slice to cake_block

Added messages and variables and extended description for food-info,
item-not-edible, not-a-food-item, food-info, set-successful, set-failed.

Renamed cake_slice to cake_block, because the same name is also used in
the materials interface.
Added aliases for the /ch command, added more permissions

Previously you could only use the /chealth command - now you can also
say /ch or /customhealth

Permissions added:
- set
- get
- info
- reset
- basically everything
Added static getPlugin method
Changed from v1.5.1 to 1.5.2
Some classes, not important
Added the commands, included tab feature
Info command shows you now information about the plugin
Not only is printing line breaks, but also player names.
Made no sense to put it in an extra class
Moved the whole addEffects method to the FoodDataBase

There's a new class called EffectValue which contains all the
information about the effects a food item contains. Those effectvalues
are saved in the FoodValue-class, which is saved in the FoodDataBase.
This makes the getting and setting of effects way easier and the config
file doesn't have to be called all the time.
Potion Effects are now saved in the FoodDataBase
Added EffectValue to the FoodValue list
Removed templates, might add it in another version again
Added Get, Reset and Set command
EffectValue class saves all the preferences from the config file

The EffectValue class saves the type, probability, duration and
strength of a potion.