Add basic setup for locale tracking and switching.

[eldarc]

Currently there are no built in options for locale tracking/saving and switching.

There is a need to simplify integration with cookies, localStorage, sessionStorage, and enable custom functions for saving and loading the locale. Also, a simplified integration with vue-router is a requirement since prefixed URLs are a needed feature.

The implementation will follow in two stages.

• [x] Implement basic setup for routing and storage.
• [ ] Find bugs in the basic setup and implement advanced features with automatic configuration parsing and validation.

[eldarc]

Support is now added.

Further testing, bug fixing and adjustments are required.