[docs] dev: add tuto "Setting up your development environment"

doc/dev/setup_env_dev.md

+
+# Setting up your development environment
+
+Title: Setting up your development environment
+Order: 1
+Date: 2020-05-04
+Slug: setup_env_dev
+Authors: elois
+
+## Prerequisites
+
+To develop on Duniter, there is currently the following requirement:
+
+- A computer with GNU/Linux or Mac as operating system
+- Build essential tools
+- git (apt-get install git)
+- Nvm
+- Rust
+- Yarn
+
+And preferably an IDE that supports [Typescript] and [Rust] well.
+
+[Rust]: https://www.rust-lang.org/
+[Typescript]: https://www.typescriptlang.org/
+
+### Install Prerequisites
+
+Nvm:
+
+    wget -qO- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.3/install.sh | bash
+
+Rust:
+
+    curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -- -y
+
+Yarn: [installation instructions][yarn]
+
+## Build the project
+
+### Clone de repository
+
+    git clone https://git.duniter.org/nodes/typescript/duniter
+
+### Install and use the correct version of nodejs
+
+Check the required node version in the `package.json` file on line 5.
+
+If, for example, version 10 is expected, install and select it with the following command:
+
+    nvm install 10 && nvm use 10
+
+### Build the project and play automated tests
+
+**WARNING**: the 1st compilation of the project requires a lot of resources on your machine, and several long minutes, don't do anything else at the same time!
+
+Command to compile :
+
+    yarn
+
+**WARNING**: playing automated tests takes a lot of resources on your machine and those for several minutes, don't do anything else at the same time!
+
+Command to play automated tests:
+
+    yarn test
+
+If all the tests are successful, the command ends like this:
+
+    ```bash
+      777 passing (40s)
+      19 pending
+
+    Done in 43.80s.
+    ```
+
+## Configure your IDE
+
+Personally, I use VsCodium/VsCode, so I give the configuration for this IDE.
+
+### Configure VsCodium/VsCode
+
+VsCodium/VsCode natively contains everything you need for Typescript.  
+For the Rust part, I strongly recommend the following plugins:
+
+- Better TOML (identifier: `bungcip.better-toml`)
+- CodeLLDB (identifier: `vadimcn.vscode-lldb`)
+- rust-analyzer (identifier: `matklad.rust-analyzer`)
+
+The recommended ide configuration can be found in `doc/dev/vscode/settings.json`.
+
+#### Debugger configuration
+
+The recommended debugger configuration can be found in `doc/dev/.vscode/launch.json`.  
+For import it:
+
+    cp doc/dev/vscode/launch.json .vscode/launch.json
+
+You can then adapt it according to your preferences for use :)
+
+[Rust]: https://www.rust-lang.org/
+[Typescript]: https://www.typescriptlang.org/
+[yarn]: https://classic.yarnpkg.com/en/docs/install/