Document Java 16 being unsupported.

See #697

readme.md

@@ -26,9 +26,10 @@ Honest recommendation: If you don't understand what any or most of that means th
 
 ## How to Run
 
-If you don't have an up-to-date Java installation install [OpenJDK](https://adoptopenjdk.net/?variant=openjdk8&jvmVariant=openj9) (the JRE will suffice).
+You need Java (at least 8, at most 15). If you don't have an up-to-date Java installation install [OpenJDK](https://adoptopenjdk.net/?variant=openjdk8&jvmVariant=openj9).
 
-Download the [latest release of NZBHydra 2](https://github.com/theotherp/nzbhydra2/releases/latest) for your platform ("linux" is any platform but windows). Extract it anywhere (the zip does not include a base directory) and start using the appropriate way:
+Download the [latest release of NZBHydra 2](https://github.com/theotherp/nzbhydra2/releases/latest) for your platform ("linux" is any platform but windows). Extract it anywhere (the zip does not include a base directory) and start using the
+appropriate way:
 * On Windows (64-bit) you can either start `NZBHydra2.exe` which will add a tray icon (give it some time) or `NZBHydra2 Console.exe` which will open a console window. Note: Do *not* use the folders `C:\Program Files` or `C:\Program Files (x86)`.
 * On Linux start `nzbhydra2` (currently working only on x64). You may need to `chmod +x` it first. 
 * On Mac: No executable yet, see next point