Differences v01 – v00
---------------------
_paddles are added_

- config:
  - "model" -> "paddles": array of two models is added
  - "view"  -> "paddle": one view config for both paddles is added
- ModelCircle:
  - method reset is added  
  - getter left, right, top, bottom are added
- ModelRectangle is added  
- update: paddles are added to the list of models to be updated
- ViewRectangleGraphics: new
- app:
  - ModelRectangle, ViewRectangleGraphics are added
  - model and view of paddles are added and initialized

_cleanup_
- ViewCircleGraphics: default values are changed (improved)
- ViewCircleSprite: c_sprite.antialias = true; added

Differences v02 – v01
---------------------

_collision detection and handling for paddles_

- ModelPaddle: new
- app:    ModelPaddle instead of ModelRectangle used
- ModelCircle:    setter for left, right, top, bottom
- ModelRectangle: setter for left, right, top, bottom
- collisionPaddleStage:  new
- collisionBallStage:    improved
- collisionPaddleCircle: new
- update: collisionPaddleCircle, collisionPaddleStage added


Differences v03 – v02
---------------------

_paddle control_

- config: "control" added
- ControlPaddle: new
- app: paddle controller added

Differences v04 – v03
---------------------

_game logic implemented_

- config
  - "model" -> "ball": init object for randomization
                       via concretize added
  - "model":   scores added
  - "view":    text added
  - "logic":   "winScore" added
- ModelCircle: concretization of config object 
               in reset function 
- ModelScore:  new   
- ViewText:    new
- app: ModelScore, ViewText added and initialized               
- logic: new (initLogic, ballLoss)
- collisionCircleStage: call ballLoss, when the ball 
                        is lost by one player
- app: logicInit added and initialized               

_cleanup_
- ModelRectangle: this.config, reset simplified
                  (analogous to ModelCircle)              
- ModelPaddle: reset via this.config

Differences v05 – v04
---------------------

_start button added_
- config: 
  - "init" -> "pixiImages": "imgStart" added 
  - "model" und "view": init "startButton"
- update: add start button model 
- ModelCircle: methods moveTo, start, stop added
- ViewCircleSprite: method addEventListener added
- logic:  new function "startGame" (show start button;
          enable starting a new round)
- ControlPaddle: new 
- app:
  - import controlStart
  - import an image for the start button
  - add and initialize model and view of the start button
  
Differences v06 – v05
---------------------

_add info text field_

- all JavaScript files are commented
- config: 
  - "model" -> "paddles": default names of players added
  - "model" -> "info" added
  - "view"  -> "textLarge" added
- logic: if game is over, the name of the winner is 
         show for some seconds
- ModelPaddle: attribute player is added   
- app: info field (ModelText, ViewText) is added and initialized