TestSpringConfigurationIntegrationTest, AbstractIntegrationTest

https://github.com/openMF/mifosx/pull/906 has illustrated that there are no real integration tests in Mifos X.

Contrary to the tests which (at the time of writing) are in src/integrationTest/java (which actually really are more "end-to-end" kind of tests; they call the REST API via remote (localhost) HTTP, out-of-process), these tests are integration tests in the Spring sense - to run in-process. Contrary to unit tests, which test only one/a few class and mock others, such integration tests have access to a "fully initialized" (all beans) environment.

This adds a foundation for such integration tests. In order to complete it properly, we need:

1. avoid an issue with Flyway, by moving mifosng-db/migrations/core_db into mifosng-provider/src/main/resources/sql. (BTW: I’m not sure what do with with mifosng-provider/src/main/resources and other files in mifosng-db - opinions?) The issue with Flyway appears if you delete the entire (new) mifosng-provider/src/main/resources/sql/ directory. What I've done is a hack to POC this - if we leave it like this, it means integration tests won't run database migrations, which is a shame.

2. solve the IllegalArgumentException: Not an managed type: class org.mifosplatform.accounting.closure.domain.GLClosure at org.hibernate.ejb.metamodel.MetamodelImpl.managedType(MetamodelImpl.java:200) error, which I only get from gradlew test, but not when running the TestSpringConfigurationIntegrationTest in Eclipse. I've tried to play with packagesToScan in infrastructure.xml, but it doesn't seem to work; #helpwanted!

When this is on develop, I'll try to push it one notch further, and enable it to use my https://github.com/vorburger/MariaDB4j stuff... ;-)