adding extra services functionality

[eik-dahms]

feature: users can add non dataplant services
reason: local run gitlab/ datahub instances, testing and development of instances
resolves #56

Workflow:

New Service View

An additional panel has been added where additional services are show and can be managed.

Add Service Dialog

The user can add services with or without client secret. (Depends how application is set up in gitlab)

Remove Service Dialog

User can also remove previously added service.

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This features strictly separates Dataplant services and services added by the user. Meaning the user can not change the hardcoded dataplant services or remove them. Added services are stored in a separate config file. Services with already existing URLs can not be added or changed.

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In general UI, datamodels and functionality have been altered such that no functionality was taken and everything else works as expected.

[JonasLukasczyk]

Thank you for putting this together. This will add quite a lot of code, so I want to make sure that there is no simpler way to do this. For example, is there a good reason why you added an additional datahub file instead of just updating the original one? I think you could apply all your changes to this single file instead. Making the distinction between the original and additional case causes a lot of code bloat like:

export const CredentialStore: CredentialStoreType = {
  /** manage credentials for different datahubs */
  credential_file_dataplant: CREDENTIALS_DATAPLANT, 
  credential_file_additional: CREDENTIALS_ADDITIONAL, 
  credentials: {dataplant: {}, additional: {}},