anchor.diff:  +s_mach.concurrent+ provides the +workers+ method for controlling the amount of concurrency. The number of concurrent
   workers is specified as the first parameter.
   
  -.Example 6: Using +s_mach.concurrent+ workers to transform and traverse collections:
  +.Example 3: Using +s_mach.concurrent+ workers to transform and traverse collections:
   [source,scala,numbered]
   ----
   val oomItemIdBatch = (1 to 10).toList.map(_.toString).grouped(2).toList
  
positive.code: +s_mach.concurrent+ adds an applicative workflow method for futures: +concurrently+. This method can more concisely
  express the pattern above:
  
  .Example 3: New +concurrently+ method
  [source,scala,numbered]
  ----
  for {
  
negative.code: Sadly, this code will compile and run just fine, but it will not execute concurrently. To correctly implement concurrent
  operation, the following standard pattern is used:
  
  .Example 4: Correct +Future+ concurrency:
  [source,scala,numbered]
  ----
  val f1 = read("1")
  