Draft: Make QrCodeModule configurable

This is a draft, do not start it yet :D

QrCodeModule adds a home page entry. The goal now is to configure if and at which position the module provides this entry – at the moment the module determines this completely on it's own.

Home page entries

Add a static method .provideEntries(config?:QrCodeModuleConfig) to the module expecting an optional value of an interface like this:

	export interface QrCodeModuleConfig {
		menuEntry?: 		boolean | number
	}

Use provideHomePageEntry() in that static method.

• If .provideEntries(...) is not used when importing QrCodeModule, do not provide a home page entry.
• If .provideEntries() is used without parameter provide the menu entry already defined in the module file.
• If config.provideHomepageEntry is undefined or false do not provide any home page entry.
• If config.provideHomepageEntry is true use the HomePageEntry objects as already defined in the module file.
• If config.provideHomepageEntry is a number use the HomePageEntry object as already defined in the module file, but replace the position value with the given number.

Scanner service

• The QrCodeModule already has a static method .forRoot. Please remove it and instead add provideScanService(scanService: Type<RccQrCodeScanner>) to lib/common/qr-code/qr-code.commons.ts. Update modules that used the static method QrCodeModule.forRoot() and make them use provideScanService() instead.
• Use RccQrCodeScanner as injection token.

Requirements

• When imported in features.module.ts of the HCP(doc) and pat variant, you can use QrCodeModule.provideEntries(...) to configure the positions of home page entry.
• QrCodeModule.forRoot() is no longer in use and the QR-Code-Scanner still works.