Re-think current margin setup

[ivarref]

Probably should use something like [:g (translate 15 15) ... at the top (?)

[ivarref]

Make axis rendering only grow downwards and to the right.

This means that merely something like available-width and available-height will be sent in to the axis.
The actual width and height of the chart itself will be determined based on text width & height.

[ivarref]

This should be a separate abstraction that uses scale behind the scenes.

[ivarref]

This is because both x and y scales/axis may contribute to margins.

[ivarref]

For example: Y axis labels will contribute to margins that will determine the width.

[ivarref]

IF x axis labels should be allowed to be rotated, then they also may severely contribute to height...

[ivarref]

But usually y axis (ordinal) labels will have the greatest impact on width.