Updates Angular to version 9.1
Updates most-to-all npm components
Removes deprecated components and npm commands
Updates travis node version
Adjust the whole code base to angular 9 standard
Increase TypeScipt version to 3.8
- Moves the 'spinner.component' to 'site.component'
- Replaces also the 'spinner.service' with an 'overlay.service', that handles all request to
show an element on an overlay.
