Java: Print AST query should add a synthetic ImportContainer node

[aeisenberg]

Currently, the Print AST query for Java will return all Import nodes in the top level compilation unit. However, this adds significant clutter when people view in the AST Viewer since you need to scroll in order to see the first Class or Interface node.

One suggestion to get around this is to create a synthetic ImportContainer node and add all imports to that node. This will avoid cluttering the AST.