Print inner startup exception cause to stderr
Print inner startup exception cause to stderr

Startup exceptions should have the cause printed to the stderr. Currently the full stack trace is printed to the log file, and only startup exception to the stderr - looking like this

  Exception in thread "main" com.google.enterprise.adaptor.StartupException: Failed to start application.
    at com.google.enterprise.adaptor.Application.main(Application.java:555)
    at com.google.enterprise.adaptor.AbstractAdaptor.main(AbstractAdaptor.java:61)
    at com.google.enterprise.adaptor.database.DatabaseAdaptor.main(DatabaseAdaptor.java:271)

Especially when there are some other warnings printed out to stdout/stderr, this can be confusing, so including also the inner exception in the message

googlegsa/library,googlegsa/library,googlegsa/library