Migrate to Angular 16

Improved:

• Make a standalone directive and drop of the module
• Renamed CurrencyMaskConfig to NgxCurrencyConfig
• Renamed CurrencyMaskInputMode to NgxCurrencyInputMode
• Renamed CURRENCY_MASK_CONFIG to NGX_CURRENCY_CONFIG
• Renamed CurrencyMaskDirective to NgxCurrencyDirective
• Now you can partially override the global configuration
• Stronger project typing, drop of any
• Changed project structure to build via Angular CLI
• Updated README to use provideEnvironmentNgxCurrency instead of forRoot

Broke/lost:

• Travis-CI
• standard-version (it is outdated and I still don't know what to migrate it to)
• scripts for publishing a new version
• May be something else...

Closes #152, #153, #155, #167