Improved Java metavariable support

[morgante]

For this code:

import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.MockitoJUnitRunner;
import org.springframework.mock.web.MockHttpServletRequest;
import org.springframework.security.oauth2.client.DefaultOAuth2ClientContext;
import org.springframework.security.oauth2.client.OAuth2ClientContext;

Both these should work:

import $_

import org.springframework.$_

[morgante]

So this actually works:

`import $import;` where $import <: contains `org.springframework`

But I think this is more intuitive:

import org.springframework.$_;

We should consider having an equivalence class that is able to map between the two.