Set ip and port by an env variable.

# Conflicts:
#	src/app/app.effects.ts
#	src/app/app.module.ts
#	src/app/app.reducer.ts
#	src/app/core/core.module.ts
#	src/app/shared/shared.module.ts

Mock AdminGuard

For docker containers it would be useful if any configuration variables
defining how to connect to the angular ui and how it connects to the
DSpace 7 REST endpoint could be overriden by environment variables. We
should not extend configuration by environment variables too much.

This PR closes #160

# Conflicts:
#	src/app/+search-page/search-filters/search-filter/search-filter.component.ts
#	src/app/+search-page/search-filters/search-filter/search-filter.service.ts
#	src/app/+search-page/search-service/search.service.spec.ts
#	src/app/+search-page/search-service/search.service.ts
#	src/app/app.component.spec.ts
#	src/app/app.component.ts
#	src/app/core/cache/response-cache.models.ts
#	src/app/core/core.effects.ts
#	src/app/core/core.module.ts
#	src/app/core/shared/hal-endpoint.service.ts
#	src/app/shared/services/route.service.ts
#	src/app/shared/view-mode-switch/view-mode-switch.component.spec.ts
#	src/modules/app/browser-app.module.ts
#	src/modules/app/server-app.module.ts

# Conflicts:
#	src/app/app.component.ts
#	src/app/core/core.module.ts

Search service implementation

added support for Object.entries, removed a console.log and fixed an issue where the page wouldn't reset after selecting a new filter