Updated CI worflow and readme for Angular 8

.github/workflows/nodejs-ci.yml

@@ -9,7 +9,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [8.x, 10.x, 12.x]
+        node-version: [12.x]
 
     steps:
     - uses: actions/checkout@v2

README.md

@@ -10,7 +10,7 @@ You may also ask questions about SDRangel or this web application in the [SDRang
 
 SDRangel is a Software Defined Radio (SDR) application that processes the digital samples produced by various SDR front end devices (RTL-SDR, LimeSDR, ...) using software running on commodity computers to implement radio processing functions that used to be handled by hardware e.g AM, FM demodulation... SDRangel is also capable of driving SDR transmitters in a reversed flow: it produces digital samples that are sent to a SDR transmitter (LimeSDR, HackRF...) to eventually produce a RF signal.
 
-This web application communicates with a SDRangel running instance (GUI based or headless) using its HTTP REST API. It is written based on Angular 6+ (see development section for more details).
+This web application communicates with a SDRangel running instance (GUI based or headless) using its HTTP REST API. It is written based on Angular 8.2 (see development section for more details).
 
 It can be used to remotely control a GUI based version of SDRangel and also serve as a UI for the headless version. Most of the functions can be accessed using this web interface.
 
@@ -19,8 +19,8 @@ It can be used to remotely control a GUI based version of SDRangel and also serv
 ## Step 1. Node & Git
 
 * Make sure you have [Git](https://www.git-scm.com) installed
-* Make sure you have [NodeJS 6.9+](https://nodejs.org/) or later installed on your machine
-* Make sure you have npm (Node Package Manager, comes bundled with NodeJS) at least version 5
+* Make sure you have [NodeJS 12](https://nodejs.org/) or later installed on your machine
+* Make sure you have npm (Node Package Manager, comes bundled with NodeJS) at least version 6
 
 You can check whether you already have them and your current versions by executing
 
@@ -66,7 +66,7 @@ sudo npm install npm -g
 git clone https://github.com/f4exb/sdrangelcli
 
 # install global dependencies
-sudo npm install -g @angular/cli
+sudo npm install -g @angular/cli@8
 
 # install local dependencies
 cd sdrangelcli
@@ -167,7 +167,7 @@ If you're using Chrome it might be a good idea to install the [Augury Plugin](ht
 
 ## Sdrangelcli
 
-This project was generated with [Angular CLI](https://github.com/angular/angular-cli) version 6.0.8.
+This project was generated with [Angular CLI](https://github.com/angular/angular-cli) version 8.2.
 
 ### Development server