Design layouting system

[saikyun]

When creating GUI components (e.g. menus), it is desirable to make it easy to do certain things:

• absolute positioning
• relative positioning (left, center, right aligned)
• "float" things next to each other
• grids

Currently this is not possible. Would be nice to gather more things that would be nice to do wrt layouting here.

[saikyun]

Sizes are implemented. Need to add positions too. Then use all that information when rendering / receiving events.

[saikyun]

Some initial work has been done: https://github.com/Saikyun/freja-layouting Need to start using it inside freja. Will start with menu.

[saikyun]

Now the menu is added. Seems to work so far.