Test case illustrating that declaration statements are removed in Wala

This is just something that we need to be aware of when handling the
mapping from Wala to Java source code.

See #36.
Compute variables defined in each statement

The variable names are the only way to map back to IVariableBindings
later by walking the tree.

See #33 and #35.
Compute local variables needed in a closure

The algorithm is as follows:

1) Determine all the def (basically writes) that are in the selected
statements.
2) For all those defs, return the ones that are not already part of the
parameter list.

This is very similar to the algorithm used in Extract Method.

See #33 and #35.