[chapter 06 #124] Remove Assignments to Parameters: add readme
[chapter 06 #125] Remove Assignments to Parameters: add example
[chapter 06 #126] Remove Assignments to Parameters: refactored example
[chapter 06 #127] Replace Method with Method Object: add readme
[chapter 06 #129] Replace Method with Method Object: add example
[chapter 06 #129] Replace Method with Method Object: copy complex logics into its own class
[chapter 06 #130] Replace Method with Method Object: replace method body to call a new class
[chapter 06 #131] Replace Method with Method Object: refactored example