Integrate and document building the stylesheet

Author: pabzm

.gitignore

@@ -2,3 +2,5 @@ _site
 vendor
 .bundle
 Gemfile.lock
+node_modules
+package-lock.json

README.md

@@ -12,3 +12,12 @@ The pages are rendered with Jekyll and kindly hosted by github.
 ```
 docker run -it -p 4000:4000 -v $(pwd):/site -w /site library/ruby bash -c 'bundle install && bundle exec jekyll serve -H 0.0.0.0'
 ```
+
+## Build CSS
+
+To build the stylesheets run this:
+
+```
+npm install
+npx less --clean-css="--s1 --advanced"  styles/styles.less > styles/styles.min.css
+```

package.json

@@ -0,0 +1,6 @@
+{
+  "dependencies": {
+    "less": "^4.4.0",
+    "less-plugin-clean-css": "^1.6.0"
+  }
+}