doc: add link to book
"APP.HOME.LABEL.ORIENTATION.1.HEADLINE": "Develop Custom Plugins",
"APP.HOME.LABEL.ORIENTATION.2.DETAILS": "Of course you can use Elektra also outside a C or C++ environment. Have a look at our <a href=\"/bindings/readme\">language bindings</a>! You can even write plugins in <a href=\"/plugins/jni\">Java</a>, <a href=\"/plugins/ruby\">Ruby</a>, <a href=\"/plugins/python\">Python</a>, and <a href=\"/plugins/lua\">Lua</a>.",
"APP.HOME.LABEL.ORIENTATION.2.HEADLINE": "Use Elektra outside C/C++",
- "APP.HOME.LABEL.ORIENTATION.3.DETAILS": "Of course we can! An initiative like Elektra asks periodically for <a href=\"/decisions/readme\">decisions</a>! We welcome everyone to join the <a href=\"https://github.com/ElektraInitiative/libelektra/issues\">discussions</a>!",
+ "APP.HOME.LABEL.ORIENTATION.3.DETAILS": "Of course we can! An initiative like Elektra asks periodically for <a href=\"/decisions/readme\">decisions</a>. We wrote a <a href=\"https://book.libelektra.org\">book</a> explaining all the scientific background. We welcome everyone to join the <a href=\"https://github.com/ElektraInitiative/libelektra/issues\">discussions</a>!",
"APP.HOME.LABEL.ORIENTATION.3.HEADLINE": "Can you Elaborate on the Why?",
"APP.HOME.LABEL.ORIENTATION.4.DETAILS": "This website does not only contain the news and documentation around Elektra. It does also comprise a service that allows for sharing, searching, converting and downloading of configuration snippets in various formats. To search for a snippet, navigate to <a href=\"https://www.libelektra.org/entries/search\">snippet search</a>. Uploading new snippets requires an account, which you can register <a href=\"/auth/login\">here</a>. All snippets have the <a href=\"/devgettingstarted/license\">BSD license</a> and are available in different formats in a <a href=\"https://snippets.libelektra.org\">git repository</a>.",
"APP.HOME.LABEL.ORIENTATION.4.HEADLINE": "Sharing of Configuration Snippets",
