wego: Incorrect table alignment under some terminal emulators due to double-width characters

This is a followup to discussion on Alacritty commit 3ad68699 (Alacritty is a “cross-platform, GPU-accelerated terminal emulator”).

The problem is that, in some terminals, wego 2.0 table alignment suffers from the width of the unicode characters used (cloud, sun, etc). See for yourself:

• GNOME Terminal:
  
• Alacritty:
  

To me that looked like a bug in Alacritty, but its main developer, @jwilm, comments that:

I believe this is a bug with wego. They don’t account that terminals may display a cloud as 1 or 2 columns. GNOME Terminal appears to think the cloud icons are only single width. Alacritty (correctly) handles them as double width. We are using the Unicode 9 definitions for wide chars, so that may account for the difference.

In the wego emoji frontend,

ret = append(ret, fmt.Sprintf("%v %v %v", cur[1], icon[0], c.formatTemp(cond)))

you can see that there’s a space after the icon in the Sprintf format string. It’s not visible in GNOME Terminal because it’s under the emoji. You can see it in Alacritty because we account for the double width characters.

wego should be using the goto functionality of terminals to handle both cases.