more convenient api for sizing rows and columns

[jwkvam]

It's clunky having to set the size of each row and column individually. It would be easier to read and write to set them in one line. For example let's try setting the rows to have sizes "auto", "1fr", "2fr".

Current api:

app.rows[0].auto()
app.rows[1].fraction(1)
app.rows[2].fraction(2)

Strings?

app.rows = ['auto', '1fr', '2fr']

Functions/properties?

app.rows = [auto, fraction(1), fraction(2)]

• poll users when asking them