Blender Git Loki

Fix bad loss of precision when manually editing values in numbuttons.

While drawing nice 'rounded' values is OK also for 'low precision'
editing like dragging and such, it's quite an issue when you type in a
precise value, validate, edit again the value, and find a rounded
version of it instead of what you typed in!

So now, *only when entering textedit of num buttons*, we always get the highest
reasonable precision for floats (and use exponential notation when
values are too low or too high, to avoid tremendous amounts of zero's).