Identify primary topic of JSON-LD response (see #257 and #230)

Use JSON-LD `@id` keyword and `foaf:primaryTopic` property to
identify the main resource that a (multi-entity, `@graph`) JSON-LD
response is about (e.g. the resource, the person, etc.)
Fix type information in views: use type of primary topic (see #257)
Only add primary topic info if there are multiple entities (#257)
Pass alias suffix to index script, optionally skip aliasing (#191)

This commit fixes an issue with the automatic alias updates: after
indexing lobid-resources, the alias was updated before lobid-items
were indexed into the same index, resulting in an incomplete index
until indexing lobid-items was done.

This commit also simplifies the alias handling: previously, there
was a custom mapping from index names to aliases. Instead, we now
just remove the timestamp from the index name to create the alias.
Merge pull request #313 from fsteeg/master

Add `\n` characters to `@Description` for improved display in IDE
Merge pull request #312 from fsteeg/issue-191-suffix

Pass alias suffix to index script, optionally skip aliasing
Merge pull request #306 from fsteeg/issue-257-topic

Identify primary topic in JSON-LD response and fix type information in views
Move config values to config file to simplify staging deployment

Specify in `application.conf`:

- application URL (for context file reference)
- index suffix (e.g. `-staging`)
- elasticsearch server, port, and cluster