misc/ Update angular material HOW TO guide

Author: maximegris

HOW_TO.md

@@ -14,6 +14,11 @@ ng add ngx-bootstrap
 
 ### How to install Angular Material
 
+Replace temporarily custom builders by default ones in `angular.json`
+
+@angular-builders/custom-webpack:browser => @angular-devkit/build-angular:browser \
+@angular-builders/custom-webpack:dev-server => @angular-devkit/build-angular:dev-server
+
 Add Angular Material using `ng add` command:
 
 ``` bash
@@ -24,16 +29,11 @@ You will get the following questions:
 ``` bash
 ? Choose a prebuilt theme name, or "custom" for a custom theme: *Choose any theme you like here*
 ? Set up global Angular Material typography styles? *Yes* 
-? Set up browser animations for Angular Material? *Yes*
+? Set up browser animations for Angular Material? *Do not include / error if you choose Include*
 ```
-Angular Material will start installing, but you will get the following error after installation:
+Angular Material Library is now installed in your project.
 
-``` bash
-Your project is not using the default builders for "build". The Angular Material schematics cannot add a theme to the workspace configuration if the builder has been changed.
-```
-*No need to Panic!* Just add your desired theme in style.scss:
+Put back custom builders in `angular.json`
 
-``` bash
-@import '@angular/material/prebuilt-themes/indigo-pink.css'
-```
-Angular Material Library is now installed in your project.
+@angular-devkit/build-angular:browser => @angular-builders/custom-webpack:browser \
+@angular-devkit/build-angular:dev-server => @angular-builders/custom-webpack:dev-server

README.md

@@ -140,6 +140,10 @@ Finally from VsCode press **Ctrl+Shift+D** and select **Application Debug** and
 
 Please note that Hot reload is only available in Renderer process.
 
+## Want to use Angular Material ? Ngx-Bootstrap ?
+
+Please refer to [HOW_TO file](./HOW_TO.md)
+
 ## Branch & Packages version
 
 - Angular 4 & Electron 1 : Branch [angular4](https://github.com/maximegris/angular-electron/tree/angular4)