Merge 6.1.beta2 into stable

Conflicts:
	CHANGELOG.md
	INSTALL.md
	documentation/FreeBSD-FreeNAS-Install.md
	documentation/INSTALL.md
	libresonic-assembly/pom.xml
	libresonic-booter/pom.xml
	libresonic-installer-debian/pom.xml
	libresonic-installer-mac/pom.xml
	libresonic-installer-rpm/pom.xml
	libresonic-installer-windows/pom.xml
	libresonic-main/pom.xml
	libresonic-rest-api/pom.xml
	libresonic-sonos-api/pom.xml
	pom.xml

libresonic-assembly/pom.xml

@@ -9,7 +9,7 @@
     <parent>
         <groupId>org.libresonic.player</groupId>
         <artifactId>libresonic</artifactId>
-        <version>6.1.rc1</version>
+        <version>6.1</version>
     </parent>
 
     <dependencies>