_content/doc: fix module and tutorial bugs and clean up flow

For golang/go#44241

- Fix issues 2, 3, 8, 16, 17, 18 from golang/go#44241

Other changes in multiple topics:

- In markdown, replace HTML anchor tags with {#anchor} tags.
- In a few places, add content to clarify that module path must
  be a location from which the module can be downloaded.
- Where it was missing, add example.com domain to example module
  paths. Hopefully, this will reinforce the idea that the module
  path should typically include a domain. Docs will use
  something that looks like a domain name for module path.
- Add more cross-references from tutorial to references for
  packages and commands.
- Rewrite a few links so that they include the topic title,
  rather than simply inline text. Left those links whose
  destinations are references -- the item's name seems to
  suggest that a reference is at the destination.
- Remove domain name from golang.org doc links, leaving root
  directory. Such as /cmd/go/* or /doc/modules/*
- Add path up to root for all links in the same domain.
  Some were linking by file name only.
- Change standard library links from golang.org to pkg.go.dev.

Changes in the module tutorial:

- Add text to help clarify that there should be a hello and
  greetings directory as siblings in their directory hierarchy.
  Some users thought one should be subordinate to the other.
- Where needed, reorder steps so that `go mod init` is run before
  code is added. This is intended to reinforce the importance of
  the module's presence.
- In require/replace steps, have the user use `go mod edit`
  rather than editing the go.mod file in an editor. The tools
  are more likely to yield a functioning result.
- Where possible/appropriate, change module directive link
  destinations from "Modules reference" to go.mod reference.
- Change "run the code" steps so that they all use `go run .`
  rather than `go build` or `go run <filename>`. This removes
  the impedance of explanation and more commands, while
  moving the explanation of `go build` and `go install` to
  a separate topic where they share a clearer context.
- Add a "Conclusion" topic with a few links. The tutorial ended
  rather abruptly before.
- Minor edits to remove some redundant language.

Change-Id: I93055035d73c362ba73edea458fc53bc45e66512
Reviewed-on: https://go-review.googlesource.com/c/website/+/297531
Trust: Steve Traut <straut@google.com>
Run-TryBot: Steve Traut <straut@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/_content/doc/tutorial/module-conclusion.html b/_content/doc/tutorial/module-conclusion.html
new file mode 100644
index 00000000..f86af3af
--- /dev/null
+++ b/_content/doc/tutorial/module-conclusion.html
@@ -0,0 +1,31 @@
+<!--{
+    "Title": "Conclusion",
+    "Path":  "/doc/tutorial/module-conclusion"
+}-->
+
+<p>
+  In this tutorial, you wrote functions that you packaged into two modules: one
+  with logic for sending greetings; the other as a consumer for the first.
+</p>
+
+<aside class="Note">
+  <strong>Note:</strong> This topic is part of a multi-part tutorial that begins
+  with <a href="/doc/tutorial/create-module.html">Create a Go module</a>.
+</aside>
+
+<p>
+	For more on managing dependencies in your code, see
+	<a href="/doc/modules/managing-dependencies">Managing dependencies</a>. For
+	more about developing modules for others to use, see
+	<a href="/doc/modules/developing">Developing and publishing modules</a>.
+</p>
+
+<p>For many more features of the Go language, check out the
+  <a href="https://tour.golang.org/welcome/1">Tour of Go</a>.
+</p>
+
+<p class="Navigation">
+  <a class="Navigation-prev" href="/doc/tutorial/compile-install.html"
+    >&lt; Compile and install the application</a
+  >
+</p>