[charts] Replace Aspect ratio scaling with dual independent Axes scaling

The aspect ratio scaling has worked pretty well. However, there are some use cases it is not so strong:

1) Multiple different chart types are nearly impossible to align widths since the different chart types each have different aspect ratios, each grows at a different (height/width) ratio depending on width. So you can just say 'width:100%' on both charts. There will be exactly, one page width that both charts will be the same size (and hopefully at that width, the size ratios will be what is expected).
2) Layouts with smaller sections (like 1/3 page width columns) get messed up at different sizes. For example, on server overview we had some page sizes where the x-axis was cut-off due to the width expanding and also expanding the height (according to the aspect ratio).
3) Fonts get scaled and look out of proportion to original intended font size.