Add Nix installation instructions to CLI README (#232)

add Arch Linux, Debian and Nix platforms installation instructions to README

Author: lucperkins

refinery_cli/README.md

@@ -3,37 +3,78 @@
 Run Refinery migrations via cli.
 
 ## Installation
-Install refinery_cli via cargo.
+
+The binary name for `refinery_cli` is `refinery`.
+
+**[Archives of precompiled binaries for refinery are available for Windows,
+macOS and Linux.](https://github.com/rust-db/refinery/releases/)** Linux and
+Windows binaries are static executables. Users of platforms not explicitly
+mentioned below are advised to download one of these archives.
+
+### Debian/Ubuntu
+
+If you're a **Debian** user (or a user of a Debian derivative like **Ubuntu**),
+then ripgrep can be installed using a binary `.deb` file provided in each
+[refinery_cli release](https://github.com/rust-db/refinery/releases/).
 
 ```sh
-cargo install refinery_cli
+$ curl -LO https://github.com/rust-db/refinery/releases/download/0.8.4/refinery_0.8.4_amd64.deb
+$ sudo dpkg -i refinery_0.8.4_amd64.deb
+```
+
+### Arch Linux
+
+If you're an **Arch Linux** user, then you can install
+the [`refinery_cli`](https://aur.archlinux.org/packages/refinery_cli) package from AUR:
+
+```sh
+$ yay refinery_cli
+```
+
+### NixOs
+
+If you're a **Nix** user, you can install ripgrep via
+the [`refinery-cli`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/tools/refinery-cli/default.nix) package:
+
+```sh
+$ nix-env -iA refinery-cli
+```
+
+### Cargo.
+
+If you're a **Rust programmer**, `refinery_cli` can be installed with `cargo`.
+
+
+```sh
+$ cargo install refinery_cli
 ```
 
 ## Usage
+
 Setup your database type and access credentials with `setup`.
 
 ```sh
-refinery setup
+$ refinery setup
 ```
 
 After that, just run your migrations giving your config file with `-c` flag (by defaults it is the `refinery.toml` generated by the setup) and migrations dir with `files -p $dir`.
 
 ```sh
-refinery migrate -c sqlite_refinery.toml -p ./sql_migrations
+$ refinery migrate -c sqlite_refinery.toml -p ./sql_migrations
 ```
 
 ### Running via database uri
 
 To run migrations from a database [uri](http://www.postgresql.org/docs/current/static/libpq-connect.html#LIBPQ-CONNSTRING) (like: postgres://user_name:passwd@hostname:5432/myDB ) stored in an environment variable DB_URI.
 
 ```sh
-refinery migrate -e DB_URI -p ./sql_migrations
+$ refinery migrate -e DB_URI -p ./sql_migrations
 ```
-This option is also useful when running refinery inside a docker container, where you usually have the db connection info stored as an environment variable.  
 
+This option is also useful when running refinery inside a docker container, where you usually have the db connection info stored as an environment variable.
 
 For more info and migration options run.
 
 ```sh
-refinery migrate --help
+$ refinery migrate --help
 ```