Update hooks in installation UI workflow

The changes in the ```Hooks``` module are due to needed API in installation UI.

Following hooks are called from ```ProductControl``` module, the rest is called from the installation clients ```installation``` and ```inst_finish``` in ```yast-installation``` package:
* installation_start
* before_setup_dhcp
* after_setup_dhcp
* before_complex_welcome
* after_complex_welcome
* before_system_analysis
* after_system_analysis
* before_installation_options
* before_disk_proposal
* after_disk_proposal
* before_timezone
* after_timezone
* before_new_desktop
* after_new_desktop
* before_user_first
* after_user_first
* before_root_first
* after_root_first
* before_initial_installation_proposal
* after_initial_installation_proposal
* before_prepareprogress
* after_prepareprogress
* before_prepdisk
* after_prepdisk
* before_deploy_image
* after_deploy_image
* before_kickoff
* after_kickoff
* before_rpmcopy
* after_rpmcopy
* before_addon_update_sources
* after_addon_update_sources
* before_extrasources
* after_extrasources
* before_save_hardware_status
* after_save_hardware_status