Add development manual

Author: PavelZubkov

README.md

@@ -0,0 +1,49 @@
+# Namespace for MAM based projects
+
+## Development
+
+### Local
+
+1. Update NodeJS to LTS
+2. Clone [MAM repository](https://github.com/hyoo-ru/mam) and install dependencies via npm or yarn
+
+```bash
+git clone https://github.com/hyoo-ru/mam.git ./mam
+cd ./mam
+npm install
+```
+
+3. Clone [this repository](https://github.com/aspirity-ru/mam_aspirity) to `./mam/aspirity`
+
+```bash
+git clone https://github.com/aspirity-ru/mam_aspirity.git ./aspirity
+```
+
+4. Build the project you want `npm run start aspirity/<project-name>`
+
+5. Run dev server `npm run start`
+6. Open url `http://127.0.0.1:9080`
+7. Disable cache in devtools
+8. Select project in browser
+
+### Gitpod
+
+1. Open [![Gitpod Online Dev Workspace](https://img.shields.io/badge/Gitpod-Online--Dev--Workspace-blue?logo=gitpod)](https://gitpod.io/#https://github.com/hyoo-ru/mam)
+2. Install recommended plugins
+3. And continue from point 3 in the Local section
+
+### Setup VSCode
+- Use MAM directory as root of your project in editor
+- [Install VScode intellisense plugin for *.view.tree files](https://marketplace.visualstudio.com/items?itemName=valikov.tree-language-service)
+- [Install plugin for *.tree files](https://open-vsx.org/extension/nin-jin/vscode-language-tree)
+- [Install .editorconfig plugin](https://open-vsx.org/extension/EditorConfig/EditorConfig)
+
+### How to make VSCode support multiple GIT repositories
+
+1. Create `./mam/.gitmodules` file with similar content. 
+```
+[submodule "aspirity_restmock"]
+    path = aspirity/restmock
+    url = git@github.com:aspirity-ru/aspirity_restmock.git
+```
+2. Edit name, path and link as needed. The file can contain many submodules