anchor.diff:  
   This can be changed with the <<Usage Help API,Help API>> for reordering sections. For example:
   
  -[source,java]
  +.Java
  +[source,java,role="primary"]
   ----
   import static picocli.CommandLine.Model.UsageMessageSpec.SECTION_KEY_AT_FILE_PARAMETER;
   import static picocli.CommandLine.Model.UsageMessageSpec.SECTION_KEY_COMMAND_LIST_HEADING;
  -import static picocli.CommandLine.Model.UsageMessageSpec.SECTION_KEY_OPTION_LIST_HEADING;
   
   @Command(name = "myapp", showAtFileInUsageHelp = true,
           mixinStandardHelpOptions = true, description = "Example command.")
  
positive.code:   or:  ln [OPTION]... -t DIRECTORY TARGET...  (4th form)
  ----
  To produce a synopsis like the above, specify the literal text in the `customSynopsis` attribute:
  [source,java]
  ----
  @Command(synopsisHeading = "", customSynopsis = {
          "Usage: ln [OPTION]... [-T] TARGET LINK_NAME   (1st form)",
  
negative.code: 
  === Section Headings
  Section headers can be used to make usage message layout appear more spacious. The example below demonstrates the use of embedded line separator (`%n`) format specifiers:
  
  .Java
  [source,java,role="primary"]
  ----
  @Command(name = "commit",
           sortOptions = false,
           headerHeading = "Usage:%n%n",
           synopsisHeading = "%n",
           descriptionHeading = "%nDescription:%n%n",
           parameterListHeading = "%nParameters:%n",
           optionListHeading = "%nOptions:%n",
           header = "Record changes to the repository.",
           description = "Stores the current contents of the index in a new commit " +
                   "along with a log message from the user describing the changes.")
  class GitCommit { /* ... */ }
  ----
  
  .Kotlin
  [source,kotlin,role="secondary"]
  ----
  @Command(name = "commit",
           sortOptions = false,
           headerHeading = "Usage:%n%n",
           synopsisHeading = "%n",
           descriptionHeading = "%nDescription:%n%n",
           parameterListHeading = "%nParameters:%n",
           optionListHeading = "%nOptions:%n",
           header = ["Record changes to the repository."],
           description = ["Stores the current contents of the index in a new commit " +
                   "along with a log message from the user describing the changes."])
  class GitCommit { /* ... */ }
  ----
  
  The usage help message generated from this class is shown below in <<Expanded Example>>.
  
  
  