Ensure tabwriter output is compatible with colorized text

[James Bowes]

#181 Fixed a license incompatibility, but may have lead to problems with output.

If I remember correctly, ansiterm's tabwriter was chosen to make sure we could align output with formatting characters, as text/tabwriter was not ansii control character aware.

Verify this, see if it still matters, and either find or write a license compatible ansii aware tabwriter.