Create web pages & API integration for System Settings.
Changes:

General Settings - completed UI changes for the following pages
Hostname - Get/Update hostname settings

License - Get/Update AMP system license

Date & Time - Get/Update system datetime settings using datepicker & timepicker, along with that NTP settings are also completed.

Log Settings - Get/Update log settings for the system, Option to configure the Remote syslog host also addded.

Backup & Restore - System backup is completed, Restore status API integrated, Restore is yet to be completed.
Overall general settings page also revamped with minimal menus.

The supporting services, interceptors and constants are created accordingly.

The changes are tested locally.