[Doc] nix install option

close #248

Signed-off-by: Lîm Tsú-thuàn <[email protected]>

docs/start/install.md

@@ -69,6 +69,14 @@ The installer downloads the plug-in files from the WasmEdge release on GitHub, u
 AI plug-ins for WasmEdge, such as the `OpenVINO backend` or `PyTorch backend` for `WASI-NN` plug-ins, have additional dependencies on the `OpenVINO` or `PyTorch` runtime libraries. [See the next section](#install-wasmedge-plug-ins-and-dependencies) for commands to install the plug-in dependencies.
 :::
 
+#### Install via Nix
+
+For nix/nixos users, we also provide a `flake.nix` in repository, so you can install WasmEdge via:
+
+```bash
+nix profile install github:WasmEdge/WasmEdge
+```
+
 ### Windows
 
 For `Windows 10`, you could use Windows Package Manager Client (aka `winget.exe`) to install WasmEdge with one single command in your terminal.
@@ -125,8 +133,8 @@ WasmEdge uses plug-ins to extend its functionality. If you want to use more of W
 
 ### The logging plug-in
 
-The `wasi_logging` plug-in supports the [log::Log](https://crates.io/crates/log) Rust API.
-It allows [log::Log](https://crates.io/crates/log) in Rust code to be compiled to Wasm and to run in WasmEdge.
+- The `wasi_logging` plug-in supports the [log::Log](https://crates.io/crates/log) Rust API.
+- It allows [log::Log](https://crates.io/crates/log) in Rust code to be compiled to Wasm and to run in WasmEdge.
 
 ```bash
 curl -sSf https://raw.githubusercontent.com/WasmEdge/WasmEdge/master/utils/install.sh | bash -s -- --plugins wasi_logging
@@ -243,8 +251,8 @@ Then, go to [WASI-Crypto in Rust chapter](../develop/rust/wasicrypto.md) to see
 
 ### WasmEdge OpenCV mini Plug-in
 
-The WasmEdge OpenCV Mini plug-in supports a subset of OpenCV APIs in a [Rust API](https://github.com/second-state/opencvmini).
-It is essential for developing image processing / vision AI applications in WasmEdge.
+- The WasmEdge OpenCV Mini plug-in supports a subset of OpenCV APIs in a [Rust API](https://github.com/second-state/opencvmini).
+- It is essential for developing image processing / vision AI applications in WasmEdge.
 
 ```bash
 curl -sSf https://raw.githubusercontent.com/WasmEdge/WasmEdge/master/utils/install.sh | bash -s -- --plugins wasmedge_opencvmini