docs: improve monorepo docs

Signed-off-by: Carlos A Becker <caarlos0@users.noreply.github.com>

www/docs/customization/monorepo.md

@@ -5,12 +5,18 @@
 
 If you want to use GoReleaser within a monorepo and use tag prefixes to mark "which tags belong to which sub project", GoReleaser has you covered.
 
-## Premise
+## Premises
 
-You create your tags like `subproject1/v1.2.3` and `subproject2/v1.2.3`.
+You project falls into either one of these categories:
+
+1. tags are like `subproject1/v1.2.3` and `subproject2/v1.2.3`;
+1. tags are like `@user/thing@v1.2.3` (for a NPM package, for example)
+  and `v1.2.3` for the rest of the (Go) code.
 
 ## Usage
 
+### Category 1
+
 You'll need to create a `.goreleaser.yaml` for each subproject you want to use GoReleaser in:
 
 ```yaml
@@ -24,13 +30,13 @@ monorepo:
 
 Then, you can release with (from the project's root directory):
 
-```sh
+```bash
 goreleaser release --rm-dist -f ./subproj1/.goreleaser.yaml
 ```
 
 Then, the following is different from a "regular" run:
 
-- GoReleaser will then look if current commit has a tag prefixed with `subproject1`, and also the previous tag with the same prefix;
+- GoReleaser will then look if current commit has a tag prefixed with `subproject1`, and the previous tag with the same prefix;
 - Changelog will include only commits that contain changes to files within the `subproj1` directory;
 - Release name gets prefixed with `{{ .ProjectName }} ` if empty;
 - All build's `dir` setting get set to `monorepo.dir` if empty;
@@ -40,3 +46,23 @@ Then, the following is different from a "regular" run:
 
 The rest of the release process should work as usual.
 
+
+### Category 2
+
+You'll need to create a `.goreleaser.yaml` for your Go code in the root of the
+project:
+
+```yaml
+# .goreleaser.yaml
+monorepo:
+  tag_prefix: v
+```
+
+Then, you can release with:
+
+```bash
+goreleaser release --rm-dist
+```
+
+GoReleaser will then ignore the tags that are not prefixed with `v`, and it
+should work as expected from there on.