Rename KeyboardComponent to KeypadComponent
Rename KeyboardService to KeypadService
Split LayoutComponent into LayoutPlayerComponent and
LayoutPagesComponent
Prepare the introduction of an additional keyboard

Reduce the number of input parameters in FloatingKeyboardComponent
Move double-used method to KeyboardService

This was necessary after the surrounding element container with its
styles and classes was deleted

This helps to divide the code of the element container into smaller
meaningful units.
In addition, each element can be given its own form group.