Update dependencies for rdf-microdata to 2.0 and rdf-turtle to 1.1.5.
Version 1.1.2.
Use standard gem build/release targets.
Release 1.1.2

Updated dependencies:

* json-ld 1.1.7
* rdf 1.1.7
* rdf=microdata 2.0
* rdf-rdfa 1.1.5
* rdf-rdfxml 1.1.3
* rdf-trig 1.1.3
* rdf-turtle 1.1.5
* sparql 1.1.4
* sparql-client 1.1.3

Add rdf-reasoner gem dependency.