This commit (obviously non-atomic) cleans LIEF's code base by:
- Using pointer semantics (`std::unique_ptr<>`)
- Using LEAF boost error in the binary stream
- Reducing the scope of the iterators (`it_section`, ...)
- Removing `Structures.hpp` from the public headers
- etc
PE's DATA_DIRECTORY_DEBUG does not define a single debug entry, but
a list of struct pe_debug entries (the number of entries is determined
by the data directory's size).
This commit reflect this layout by returning a vector<> when calling
PE.debug()
Romain Thomas