Introduce serviceWorker, disabled by default

exampleSite/config.toml

@@ -97,3 +97,7 @@ enableGitInfo = true
   # Portable links meant to work with text editors and let you write markdown without {{< relref >}} shortcode
   # Theme will print warning if page referenced in markdown does not exists.
   BookPortableLinks = true
+
+  # /!\ This is an experimental feature, might be removed or changed at any time
+  # (Optional, experimental, default false) Enables service worker that caches visited pages and resources for offline use.
+  BookServiceWorker = true

exampleSite/config.yaml

@@ -93,3 +93,7 @@ params:
   # Portable links meant to work with text editors and let you write markdown without {{< relref >}} shortcode
   # Theme will print warning if page referenced in markdown does not exists.
   BookPortableLinks: true
+
+  # /!\ This is an experimental feature, might be removed or changed at any time
+  # (Optional, experimental, default false) Enables service worker that caches visited pages and resources for offline use.
+  BookServiceWorker: true

exampleSite/resources/_gen/assets/scss/example/book.scss_50fc8c04e12a2f59027287995557ceff.json

@@ -0,0 +1 @@
+{"Target":"book.min.284c8fc21ced13c579d9027a9d14893c56b243c6045001180391cebb4cc36ab8.css","MediaType":"text/css","Data":{"Integrity":"sha256-KEyPwhztE8V52QJ6nRSJPFayQ8YEUAEYA5HOu0zDarg="}}