Added MultiTest installation chapter.

Author: DariuszDepta

docs/multi-test/installation.md

@@ -0,0 +1,63 @@
+---
+sidebar_position: 1
+---
+
+# Installation
+
+**MultiTest** is as a [Rust] library named [cw-multi-test] and is hosted on [crates.io].
+
+## Usage
+
+To use **MultiTest** in your project, simply add it as a **development dependency** to **Cargo.toml** file:
+
+```toml title="Cargo.toml"
+[dev-dependencies]
+cw-multi-test = "3"
+```
+
+:::warning
+
+**MultiTest** is a **TESTING** library and should **ALWAYS** be added to your project
+as a **DEVELOPMENT DEPENDENCY** in section **`[dev-dependencies]`** of the **Cargo.toml** file.
+  
+**MultiTest** <u>**IS NOT**</u> designed to be used in production code on a real-life blockchain.
+
+:::
+
+## Prerequisites
+
+### Rust and Cargo
+
+The only prerequisite to test smart contracts using **MultiTest** is having [Rust and Cargo] installed.
+
+:::info
+
+We recommend installing Rust using the official [rustup installer]. This makes it easy
+to stay on the most recent version of Rust and Cargo.
+  
+:::
+
+### Tarpaulin and cargo-nextest
+
+Optionally, you may want to install [Tarpaulin] for measuring code coverage, and [cargo-nextest] for
+running tests faster with a clean and beautiful user interface.
+
+Installing **Tarpaulin**:
+
+```shell
+cargo install cargo-tarpaulin
+```
+
+Installing **cargo-nextest**:
+
+```shell
+cargo install cargo-nextest
+```
+
+[rustup installer]: https://rustup.rs
+[Rust and Cargo]: https://www.rust-lang.org/tools/install
+[Rust]: https://www.rust-lang.org
+[Tarpaulin]: https://github.com/xd009642/tarpaulin
+[cargo-nextest]: https://nexte.st
+[cw-multi-test]: https://crates.io/crates/cw-multi-test
+[crates.io]: https://crates.io