Update external links

Author: joto

_libosmium_manual/02_dependencies.md

@@ -231,7 +231,7 @@ for some untested experimental code.
 
 ### LZ4 (from 2.16.0)
 
-The [LZ4](https://lz4.github.io/lz4/) library is needed if you want to use
+The [LZ4](https://lz4.org/) library is needed if you want to use
 LZ4 compression in PBF files. This is an optional feature available from
 libosmium version 2.16.0.
 

_libosmium_manual/05_using.md

@@ -128,7 +128,7 @@ For version 2.3.0 and above you don't need much:
 * Include files: `osmium/io/any_input.hpp`, `osmium/io/any_output.hpp`, `osmium/io/pbf_input.hpp`, `osmium/io/pbf_output.hpp`
 
 If you want support for lz4 compression in PBF blobs, you also need the
-[LZ4 library](https://lz4.github.io/lz4/).
+[LZ4 library](https://lz4.org/).
 
 For versions up to 2.2 you need some more libraries:
 

_osmium_tool_manual/02_installation.md

@@ -33,5 +33,5 @@ Packages for several Fedora versions
 ### Archlinux
 
 Packages can be installed from [AUR](https://aur.archlinux.org/):
-[osmium-tool](https://aur.archlinux.org/packages/osmium-tool/)
+[osmium-tool](https://aur.archlinux.org/packages/osmium-tool)
 

libosmium/index.html

@@ -52,7 +52,7 @@ <h2>Download</h2>
 <ul>
     <li><a href="https://packages.debian.org/source/libosmium">Debian/Ubuntu</a> (including Debian backports)</li>
     <li><a href="https://src.fedoraproject.org/rpms/libosmium">Fedora</a></li>
-    <li><a href="https://aur.archlinux.org/packages/libosmium/">Archlinux</a></li>
+    <li><a href="https://aur.archlinux.org/packages/libosmium">Archlinux</a></li>
     <li><a href="https://formulae.brew.sh/formula/libosmium">macOS (Homebrew)</a></li>
 </ul>
 

pyosmium/index.html

@@ -47,7 +47,7 @@ <h2>Download</h2>
 <ul>
     <li><a href="https://packages.debian.org/source/pyosmium">Debian/Ubuntu</a> (including Debian backports)</li>
     <li><a href="https://src.fedoraproject.org/rpms/pyosmium">Fedora</a></li>
-    <li><a href="https://aur.archlinux.org/packages/pyosmium/">Archlinux</a></li>
+    <li><a href="https://aur.archlinux.org/packages/pyosmium">Archlinux</a></li>
 </ul>
 
 <a href="https://repology.org/project/pyosmium/versions"><img src="https://repology.org/badge/tiny-repos/pyosmium.svg" alt="Packaging status"/></a>