chore(NA): @kbn/pm new commands to support development on Bazel packages

docs/developer/getting-started/index.asciidoc

@@ -66,7 +66,8 @@ yarn kbn bootstrap --force-install
 
 (You can also run `yarn kbn` to see the other available commands. For
 more info about this tool, see
-{kib-repo}tree/{branch}/packages/kbn-pm[{kib-repo}tree/{branch}/packages/kbn-pm].)
+{kib-repo}tree/{branch}/packages/kbn-pm[{kib-repo}tree/{branch}/packages/kbn-pm]. If you want more 
+information about how to actively develop over packages please read <<monorepo-packages>>)
 
 When switching branches which use different versions of npm packages you
 may need to run:
@@ -169,3 +170,5 @@ include::debugging.asciidoc[leveloffset=+1]
 include::building-kibana.asciidoc[leveloffset=+1]
 
 include::development-plugin-resources.asciidoc[leveloffset=+1]
+
+include::monorepo-packages.asciidoc[leveloffset=+1]

docs/developer/getting-started/monorepo-packages.asciidoc

@@ -0,0 +1,61 @@
+[[monorepo-packages]]
+== {kib} Monorepo Packages
+
+Currently {kib} works as a monorepo composed by a core, plugins and packages.
+The latest are located in a folder called `packages` and are pieces of software that 
+composes a set of features that can be isolated and reused across the entire repository.
+They are also supposed to be able to imported just like any other `node_module`.
+
+Previously we relied solely on `@kbn/pm` to manage the development tools of those packages, but we are 
+now in the middle of migrating those responsibilities into Bazel. Every package already migrated 
+will contain in its root folder a `BUILD.bazel` file and other `build` and `watching` strategies should be used.
+
+Remember that any time you need to make sure the monorepo is ready to be used just run:
+
+[source,bash]
+----
+yarn kbn bootstrap
+----
+
+[discrete]
+=== Building Non Bazel Packages
+
+Non Bazel packages can be built independently with
+
+[source,bash]
+----
+yarn kbn run build -i PACKAGE_NAME
+----
+
+[discrete]
+=== Watching Non Bazel Packages
+
+Non Bazel packages can be watched independently with
+
+[discrete]
+=== Building Bazel Packages
+
+Bazel packages are built as a whole for now. You can use:
+
+[source,bash]
+----
+yarn kbn build-bazel
+----
+
+[discrete]
+=== Watching Bazel Packages
+
+Bazel packages are watched as a whole for now. You can use:
+
+[source,bash]
+----
+yarn kbn watch-bazel
+----
+
+
+[discrete]
+=== List of Already Migrated Packages to Bazel
+
+- @elastic/datemath
+
+