Fix floating point display on terminal output

[jbencina]

Summary

The current implementation of modeslive on terminal screens creates difficult to read formatting due to floating point precision larger than the defined column widths. This PR makes an adjustment to round floating point numbers to the defined column width to improve readability. This resolves issue #178

This behavior may have been caused by #147. For visual user output it probably makes sense to at least keep some formatting in the terminal view. This PR does not affect any other internal calculations or the dump output.

The logic is:

• Determine if there is a negative sign in the output
• Account for the decimal point
• From the column width, subtract the negative sign, decimal, and one extra space to allow spacing between columns.
• Round the floating point rather than truncating for additional accuracy
• Use string formatting to maintain trailing zeros for visual improvement

Testing Done

Before: Fields not aligned with columns and spilling around

After: Fields behave correctly.

Confirmed no impact to --dump output