upgraded to ngx-translate

Initial home page content

Simple Item View Page

Add support for Communities

Rest relationships

Merge branch 'rest-relationships' of https://github.com/artlowel/dspace-angular into w2p-40416_simple-item-page

Conflicts:
	src/app/core/cache/models/normalized-item.model.ts
	src/app/core/shared/item.model.ts

moved reflect-metadata from devDependencies to dependencies in order to try and fix a travis build issue

Conflicts:
	src/app/core/cache/models/bundle-builder.ts
	src/app/core/cache/models/collection-builder.ts
	src/app/core/cache/models/item-builder.ts

Conflicts:
	src/app/core/shared/dspace-object.model.ts

ngrx-store-freeze added and configured

Opaque config: this connects to #64 and this connects to #79