Finish the first-draft of "The Jenkinsfile" section

This commit moves some unrelated portions of the original document into the
Multibranch section which is still a work in progress.

content/doc/book/pipeline/getting-started.adoc

@@ -104,6 +104,9 @@ node { // <1>
 <2> `echo` writes simple string in the Console Output.
 
 
+// Despite :sectanchors:, explicitly defining an anchor because it will be
+// referenced from other documents
+[[defining-a-pipeline-in-scm]]
 === Defining a Pipeline in SCM
 
 Complex pipelines would be cumbersome to write and maintain if you could only do
@@ -116,8 +119,8 @@ Script from SCM* option enabled by the workflow-scm-step plugin, which is one of
 the plugins that the Pipeline plugin depends on and automatically installs.
 
 Loading pipeline scripts using the `checkout scm` step leverages the
-idea of "pipeline as code," and lets you maintain pipelines using version
-control and standalone Groovy editors.
+idea of "Pipeline as code" and allows easy maintenance of Pipelines with source
+control and text-editors.
 
 To do this, select *Pipeline script from SCM* when defining the pipeline.
 
@@ -151,6 +154,7 @@ configured Pipeline project.
 
 image::pipeline-syntax-sidebar.png[Pipeline Syntax in the side-bar, role=center]
 
+[[snippet-generator]]
 === Snippet Generator
 
 The built-in "Snippet Generator" utility is helpful for creating bits of