SKOS API Support

[giraygi]

Is your feature request related to a problem? Please describe.
OLS is not capable of interpreting skos relations in a meaningful way.

Describe the solution you'd like

• Enabling SKOS Full Concept Tree Generation
• Enabling SKOS Partial Concept Tree Generation down from a certain concept
• Enabling to retrieve immediate neighbors of a particular concept based on relation type (related, broader, narrower)
• Plain Text Versions of the above three needs in order to provide human readability for alternating graph generation techniques (SCHEMA, TOPCONCEPTOF, RELATIONS)
• An immediate neighbors graph that the subject node targets based on relation type (related, broader, narrower)

Describe alternatives you've considered
A resource demanding alternative can be indexing skos relations in an alternative way.