Package tree data structure

[0xddom]

libRadar uses a tree structure to hold the classes according to the package they belong. This tree also generates the hash and the score of the library recursively.

In my mind (and inspired by the reference implementation) the module should have a public struct that acts as a public API and the actual tree is defined recursively using a private struct.

We have to generate a tree for each dex that we are handling, so it must receive a Dex as input parameter along with the api set that is used to calculate the score of each node in the tree.

The leaf nodes should contain classes and the root nodes represent the java packages.