Drop installation chapter as it requires network during build

--- ci/generate-docs.py.orig	2021-08-14 19:44:38 UTC
+++ ci/generate-docs.py
@@ -114,17 +114,6 @@ TOC = [
         "wezterm",
         "index.md",
         children=[
-            Page(
-                "Install",
-                "installation.md",
-                children=[
-                    Page("Windows", "install/windows.md"),
-                    Page("macOS", "install/macos.md"),
-                    Page("Linux", "install/linux.md"),
-                    Page("FreeBSD", "install/freebsd.md"),
-                    Page("Build from source", "install/source.md"),
-                ],
-            ),
             Page("Features", "features.md"),
             Page("Change Log", "changelog.md"),
             Page(
--- docs/contributing.md.orig	2021-08-14 19:44:38 UTC
+++ docs/contributing.md
@@ -8,7 +8,7 @@ If you're thinking of helping out, then the following 
 * [WezTerm on GitHub](https://github.com/wez/wezterm)
 * [GitHub Discussions](https://github.com/wez/wezterm/discussions)
 * [Realtime conversation with wez on Element.io/Gitter](help.html)
-* [Building from Source](install/source.html)
+* [Building from Source](https://github.com/wez/wezterm/blob/main/docs/install/source.markdown)
 * [Where to find things and hacking on wezterm](https://github.com/wez/wezterm/blob/master/CONTRIBUTING.md#contributing-to-wezterm)
 
 I like to think that I have an open mind and I try to be open to ideas,