Data fetcher factory (ExpediaGroup#41)

* Update Junit dep to Junit5

* Add support for nested queries via custom datafetchers

* Add example of custom datafetchers via spring beans

* Mark lateinit field as nullable

Use oss.sonatype repo over https rather than http

Activate release profile when deploying

v0.0.10 changelog

- add example app
- fix interface data type resolver
- add support for directives
- documentation updates

update pom

Add pom url and 0.0.6