Minor cleanups to community-supported repo docs

Capitalize GNU and alphabetize the distro list.

Author: bgilbert

readme/install.md

@@ -12,8 +12,8 @@
 * [Community Supported Repositories](#community-supported-repositories)
     * [Alpine Linux](#alpine-linux)
     * [Arch Linux](#arch-linux)
-    * [Gnu Guix Package Manager](#gnu-guix-package-manager)
     * [FreeBSD](#freebsd)
+    * [GNU Guix Package Manager](#gnu-guix-package-manager)
     * [Windows](#windows-1)
 
 ## Official Installation Methods
@@ -101,38 +101,38 @@ yay -S git-interactive-rebase-tool
 2. Extract to a known location
 3. Run `makepkg -si` from the extracted location
 
-### GNU Guix Package Manager
+### FreeBSD
 
-```shell
-guix install git-interactive-rebase-tool
-```
+FreeBSD support is provided by the community, and while attempts are made to ensure everything works on the platform, it is not officially supported. If you run into problems please [create an issue](https://github.com/MitMaro/git-interactive-rebase-tool/issues/new) describing the problem.
 
-#### In a temporary environment
+With [Ports](https://www.freebsd.org/ports/) using `pkg`
 
 ```shell
-guix shell git-interactive-rebase-tool
+pkg install interactive_rebase_tool
 ```
 
-#### In a temporary container (Linux namespace)
+#### Manual
 
 ```shell
-guix shell --container git-interactive-rebase-tool
+cd /usr/ports/devel/interactive_rebase_tool && make install clean
 ```
 
-### FreeBSD
+### GNU Guix Package Manager
 
-FreeBSD support is provided by the community, and while attempts are made to ensure everything works on the platform, it is not officially supported. If you run into problems please [create an issue](https://github.com/MitMaro/git-interactive-rebase-tool/issues/new) describing the problem.
+```shell
+guix install git-interactive-rebase-tool
+```
 
-With [Ports](https://www.freebsd.org/ports/) using `pkg`
+#### In a temporary environment
 
 ```shell
-pkg install interactive_rebase_tool
+guix shell git-interactive-rebase-tool
 ```
 
-#### Manual
+#### In a temporary container (Linux namespace)
 
 ```shell
-cd /usr/ports/devel/interactive_rebase_tool && make install clean
+guix shell --container git-interactive-rebase-tool
 ```
 
 ### Windows