Since commit `6ec399`, terminal color are lighter then before

[wenjinnn]

Hi there. This commit add a terminal_color = true as a default config value, before I upgrade to this commit, my terminal looks like: after: I think we should consider about this, Is it need to be true as default? and may be add some doc about this new config value, because it took me some time to figure out that is was this config caused these effects.