Alignment (align)
Alignment will inflate the wrapping element to use all the constraints.
This means it's not recommended to put an alignment widget inside an
unconstrained widget such as a Overflow.
The alignment accepts at most one child.
Example
border [width: 16, height: 5]
align [alignment: "centre"]
text "centre"
┌──────────────┐
│ │
│ centre │
│ │
└──────────────┘
Attributes
alignment
Valid values:
"top_left""top""top_right""right""bottom_right""bottom""bottom_left""left""centre"or"center"