EVA-1903 - Spring Boot 2 upgrade

[sundarvenkata-EBI]

• Replace Fongo with real MongoDB tests because Fongo is not supported in Spring Boot 2.1 - see here
  • Update Travis and Gitlab scripts to include Mongo installations
  • Update POMs to support "|" delimiters so that EVA mongo host for tests can be parametrized for both Travis and Gitlab
• Upgrade jackson-databind version to 2.9.7 to work with Spring Boot 2
• Adapt to API changes
  • Use Document, List instead of BasicDBObject, BasicDBList
• Use MongoDB 3.8 driver for the database-migration project
• Place MongoClient creation logic in DBAdaptorConnector in each module
• Avoid semicolons in the names of the VCF dumper exported files (Windows freaks out when it encounters such files) in VariantExporterController.java
• Import javax validation-api in POM files to enable the @Size annotation in SpringDataMongoDbProperties.java