Refactor to Typescript + Project screens + Everything else

[maartenvn]

This is a full rewrite of the core of the project to Typescript.

• Typescript is now used inside the components itself using vue-class-component and vue-property-decorators (this is what Vue CLI 3 recommends when using the class syntax)
• EchoFetch is used for requests to the API. This is a wrapper around Axios that supports easy requests using services and has great Vue bindings.
• A better and more modern project page. The data itself is still fake date until my requested backend changes are done.
• Adds a better API for opening modals & snackbars
• Adds a error handling API that follows the requested format:

  
  // A general error returns errors that are not linked to any input field.
  generalErrors: [
  {
      message: "Something general has occurred."
  }
  ],

// A field error returns an error that is linked to a body input field. // (eg name or description when creating a project) inputErrors: [ { input: "name", message: "Name cannot be longer than 3 characters." } ]

[maartenvn]

I have added a base for i18n. I would support both English & Dutch since G2 will be the key access point for all Zeus projects, so supporting multiple languages would be great.

[maartenvn]

The frontend does no longer work with the latest version of the backend (as of right now). Use a mock server with the OpenAPI specification (g2-backend/openapi) to run the frontend.