Relationships link to items via HAL links

Reverted #424

Fix issue with getSearchLink

Fix #416

Bump webpack-bundle-analyzer from 2.13.1 to 3.3.2

Group logical entity types together

Fixed filtered search page

Bumps [webpack-bundle-analyzer](https://github.com/webpack-contrib/webpack-bundle-analyzer) from 2.13.1 to 3.3.2.
- [Release notes](https://github.com/webpack-contrib/webpack-bundle-analyzer/releases)
- [Changelog](https://github.com/webpack-contrib/webpack-bundle-analyzer/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack-contrib/webpack-bundle-analyzer/compare/v2.13.1...v3.3.2)

Conflicts:
	src/app/+item-page/simple/item-types/shared/item-relationships-utils.ts
	src/app/+item-page/simple/item-types/shared/item.component.ts

Conflicts:
	src/app/core/cache/object-cache.service.ts
	src/app/core/core.module.ts
	src/app/core/data/request.service.ts
	src/app/core/shared/item.model.ts

Miscellaneous fixes for Preview Release - Part 2

Merge branch 'preview-misc-fixes-2' of https://git.atmire.com/contributions/dspace-angular into preview-misc-fixes-2

replace npm variable with dedicated script to run webpack with a larger heapspace. The variables didn't work cross-platform