Shell macro SHELL_DEFINE no longer needs new line character.
Specification has been updated accordingly.
Signed-off-by: Jakub Rzeszutko <jakub.rzeszutko@nordicsemi.no>
1. Remove old shell documentation.
2. Create documentation for new shell module.
3. Fix shell.h comments to be able to generate
API documentation.
Signed-off-by: Jakub Rzeszutko <jakub.rzeszutko@nordicsemi.no>
