Handle longer numbers

[gbakeman]

Larger or more precise numbers may cause clipping issues (as seen in nutdotnet/WinNUT-Client#150 (comment)):

Solution

Create one or more strategies/algorithms for handling long values:

• Automatically round numbers to a specific decimal place
• User-specified precision
• User-chosen standard format (from a list)
• Scale size of font automatically within user-defined limits, and make sure a manual static size is available as a property too.