Adding RestServiceSpringGradle project.

It contains the restful web service project using Spring Web + Gradle

Features:
 * Allows to use GET requests with query parameters
 * Allows to use GET requests with path parameters
 * Allows to use POST requests with Json format
 * Most of the results are returned in Json format
 * Uses Gradle to build and execute the app with 'spring-boot' plugin

**Please verify src/test/resources/How-To for start and stop details
**POSTman collection was included with some example requests