[internal] create a global inventory component.

[Daniel Coquette]

To make maintenance easier and have an extensible component, create a global inventory component.
Properties:

• can display paw (main/off paw). Defaut = true
• number of rows for mouth. Default = 0
• number of columns for mouth. Default = 0
• number of rows for body. Default = 2
• number of columns for body. Default = 1
• number of rows for pack. Default = 2
• number of columns for pack. Dfault = 3

Items can contains an inventory (like moonshore rat pack)