Auto merge of #4162 - alexcrichton:termcolor, r=matklad

Migrate from the `term` crate to `termcolor`

The API of `termcolor` fits what the system gives us much more nicely and should
be well battle-tested from ripgrep. Additionally we don't really need huge
terminfo parsers, that wasn't every really the intention of the color support
here.

diff --cc src/cargo/ops/cargo_new.rs
index cd88e52a125b9e64f6ab4e57295bec8819c6ea2d,3ac323905d492467d05dbcd976183db0d438502b..fdff07ee380c7db8ac7fb0c801fbb533cef74f4b
--- 1/src/cargo/ops/cargo_new.rs
--- 2/src/cargo/ops/cargo_new.rs
+++ b/src/cargo/ops/cargo_new.rs
@@@ -9,11 -10,9 +10,9 @@@ use serde::de
  use git2::Config as GitConfig;
  use git2::Repository as GitRepository;
  
- use term::color::BLACK;
- 
  use core::Workspace;
  use ops::is_bad_artifact_name;
 -use util::{GitRepo, HgRepo, PijulRepo, internal};
 +use util::{GitRepo, HgRepo, PijulRepo, FossilRepo, internal};
  use util::{Config, paths};
  use util::errors::{CargoError, CargoResult, CargoResultExt};