Don't refer to old Debian versions in osmcoastline doc

Author: joto

osmcoastline/index.html

@@ -45,11 +45,7 @@ <h2>Download</h2>
 <p>Current and past releases can be downloaded from
 <a href="https://github.com/osmcode/osmcoastline/releases">Github</a>.</p>
 
-<p>Packages are available for
-<a href="https://packages.debian.org/source/sid/osmcoastline">Debian Sid</a>
-(also available in
-<a href="https://packages.debian.org/source/jessie-backports/osmcoastline">Jessie
-backports</a>).
+<p>Packages are available for various Debian versions.</p>
 
 
 <h2>License</h2>