Use original fg/bg intensity values on reset

ForegroundIntensity and BackgroundIntensity were set to 0 when resetting
using "\x1b[0m". If the foreground or background color was one of the bold
colors, it was reset to the non-bold version of that color.

Updated the test to include defaultFgIntensity and defaultBgIntensity for
the "all reset"
Merge pull request #1 from gstewart/reset-fg-bg-intensity

Use original fg/bg intensity values on reset