Wrong value is returned for `systemInfo(SysInfoTextColors)` in TADS 3

[dscorbett]

In a TADS 3 game, Lectrote reports that systemInfo(SysInfoTextColors) == SysInfoTxcRGB, but it actually seems to act like SysInfoTxcNone. Here is a sample game which in Lectrote falsely claims to support colors. In other interpreters, it either correctly claims not to support colors or it successfully displays some text in green.

[curiousdannii]

This should be fixed now.