Vendor dependencies

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vendor/termcolor/README.md

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+termcolor
+=========
+A simple cross platform library for writing colored text to a terminal. This
+library writes colored text either using standard ANSI escape sequences or
+by interacting with the Windows console. Several convenient abstractions
+are provided for use in single-threaded or multi-threaded command line
+applications.
+
+[![Build status](https://github.com/BurntSushi/termcolor/workflows/ci/badge.svg)](https://github.com/BurntSushi/termcolor/actions)
+[![](https://img.shields.io/crates/v/termcolor.svg)](https://crates.io/crates/termcolor)
+
+Dual-licensed under MIT or the [UNLICENSE](https://unlicense.org/).
+
+### Documentation
+
+[https://docs.rs/termcolor](https://docs.rs/termcolor)
+
+### Usage
+
+Add this to your `Cargo.toml`:
+
+```toml
+[dependencies]
+termcolor = "1.1"
+```
+
+### Organization
+
+The `WriteColor` trait extends the `io::Write` trait with methods for setting
+colors or resetting them.
+
+`StandardStream` and `StandardStreamLock` both satisfy `WriteColor` and are
+analogous to `std::io::Stdout` and `std::io::StdoutLock`, or `std::io::Stderr`
+and `std::io::StderrLock`.
+
+`Buffer` is an in memory buffer that supports colored text. In a parallel
+program, each thread might write to its own buffer. A buffer can be printed to
+stdout or stderr using a `BufferWriter`. The advantage of this design is that
+each thread can work in parallel on a buffer without having to synchronize
+access to global resources such as the Windows console. Moreover, this design
+also prevents interleaving of buffer output.
+
+`Ansi` and `NoColor` both satisfy `WriteColor` for arbitrary implementors of
+`io::Write`. These types are useful when you know exactly what you need. An
+analogous type for the Windows console is not provided since it cannot exist.
+
+### Example: using `StandardStream`
+
+The `StandardStream` type in this crate works similarly to `std::io::Stdout`,
+except it is augmented with methods for coloring by the `WriteColor` trait.
+For example, to write some green text:
+
+```rust
+use std::io::{self, Write};
+use termcolor::{Color, ColorChoice, ColorSpec, StandardStream, WriteColor};
+
+fn write_green() -> io::Result<()> {
+    let mut stdout = StandardStream::stdout(ColorChoice::Always);
+    stdout.set_color(ColorSpec::new().set_fg(Some(Color::Green)))?;
+    writeln!(&mut stdout, "green text!")
+}
+```
+
+### Example: using `BufferWriter`
+
+A `BufferWriter` can create buffers and write buffers to stdout or stderr. It
+does *not* implement `io::Write` or `WriteColor` itself. Instead, `Buffer`
+implements `io::Write` and `termcolor::WriteColor`.
+
+This example shows how to print some green text to stderr.
+
+```rust
+use std::io::{self, Write};
+use termcolor::{BufferWriter, Color, ColorChoice, ColorSpec, WriteColor};
+
+fn write_green() -> io::Result<()> {
+    let mut bufwtr = BufferWriter::stderr(ColorChoice::Always);
+    let mut buffer = bufwtr.buffer();
+    buffer.set_color(ColorSpec::new().set_fg(Some(Color::Green)))?;
+    writeln!(&mut buffer, "green text!")?;
+    bufwtr.print(&buffer)
+}
+```
+
+### Automatic color selection
+
+When building a writer with termcolor, the caller must provide a
+[`ColorChoice`](https://docs.rs/termcolor/1.*/termcolor/enum.ColorChoice.html)
+selection. When the color choice is `Auto`, termcolor will attempt to determine
+whether colors should be enabled by inspecting the environment. Currently,
+termcolor will inspect the `TERM` and `NO_COLOR` environment variables:
+
+* If `NO_COLOR` is set to any value, then colors will be suppressed.
+* If `TERM` is set to `dumb`, then colors will be suppressed.
+* In non-Windows environments, if `TERM` is not set, then colors will be
+  suppressed.
+
+This decision procedure may change over time.
+
+Currently, `termcolor` does not attempt to detect whether a tty is present or
+not. To achieve that, please use the [`atty`](https://crates.io/crates/atty)
+crate.
+
+### Minimum Rust version policy
+
+This crate's minimum supported `rustc` version is `1.34.0`.
+
+The current policy is that the minimum Rust version required to use this crate
+can be increased in minor version updates. For example, if `crate 1.0` requires
+Rust 1.20.0, then `crate 1.0.z` for all values of `z` will also require Rust
+1.20.0 or newer. However, `crate 1.y` for `y > 0` may require a newer minimum
+version of Rust.
+
+In general, this crate will be conservative with respect to the minimum
+supported version of Rust.