Add lores to items

[Malachiel]

I would like to have lores of these items too! Thank you

[BONNe]

The description of the button is the lore.
It supports multiple lines.

From ControlPanel.yml file:

# description can include color codes using & and new lines using | and placeholders with with % at the
#    start and the end. [gamemode] in placeholders will be converted to correct string.