[player] Add UnitComponent (splitting AppComponent into 2 components)

projects/player/src/app/app.component.html

projects/player/src/app/app.component.spec.ts

projects/player/src/app/app.component.ts

projects/player/src/app/app.module.ts

projects/player/src/app/components/unit/unit.component.html

projects/player/src/app/components/unit/unit.component.scss

...cts/player/src/app/components/unit/unit.component.spec.ts

projects/player/src/app/components/unit/unit.component.ts

projects/player/src/app/directives/unit-state.directive.ts

...pp/services/element-model-element-code-mapping.service.ts