Log the inner exception thrown from JdbcMigrationResolver.resolveMigrations()

[logicbomb]

What version of Flyway are you using?

4.03

Which client are you using? (Command-line, Java API, Maven plugin, Gradle plugin, SBT plugin, ANT tasks)

Command-line

What database are you using (type & version)?

Postgres 9.4

What operating system are you using?

Ubuntu 14.04

What did you do?

(Please include the content causing the issue, any relevant configuration settings, and the command you ran)
Attempted to execute a java migration

What did you expect to see?

Helpful error message

What did you see instead?

ERROR: Unable to resolve Jdbc Java migrations in location: classpath:db/migration

It would be nice if flyway logged the inner exception thrown from JdbcMigrationResolver.resolveMigrations() I'm sure a lot of Java migration errors are a result of the java implementation and nothing to do with Flyway, but as it stands now it's tough to have any idea what's going on. Even changing the error message to include (something like) "try re-running the migration with the -X switch to see detailed logs" would be a big help.