Pagination on community page

Lookup relations - Search external sources

Upgrade Travis image to 'bionic'

remove chrome source, doesn't work anyway and doesn't seem to be needed. Remove chromium to try to solve the issue where travis can't find chrome

Fixed renamed TSLint rules

Conflicts:
	src/app/core/data/data.service.ts
	src/app/shared/form/builder/ds-dynamic-form-ui/relation-lookup-modal/search-tab/dynamic-lookup-relation-search-tab.component.ts

Upgrade angular 7

# Conflicts:
#	src/app/+collection-page/collection-form/collection-form.component.ts
#	src/app/+community-page/community-form/community-form.component.ts
#	src/app/shared/comcol-forms/comcol-form/comcol-form.component.ts

Community and collection logos

Conflicts:
	src/app/shared/shared.module.ts

Bumps [handlebars](https://github.com/wycats/handlebars.js) from 4.1.2 to 4.5.3.
- [Release notes](https://github.com/wycats/handlebars.js/releases)
- [Changelog](https://github.com/wycats/handlebars.js/blob/master/release-notes.md)
- [Commits](https://github.com/wycats/handlebars.js/compare/v4.1.2...v4.5.3

)

Signed-off-by: dependabot[bot] <support@github.com>

# Conflicts:
#	src/app/core/services/route.service.ts
#	src/app/shared/form/builder/ds-dynamic-form-ui/ds-dynamic-form-control-container.component.ts
#	src/app/shared/form/builder/form-builder.service.ts
#	src/app/shared/object-list/object-list.component.spec.ts
#	src/app/submission/submission.service.ts