pe: Support multiple debug directories and VCFeature, Repro, ExDllCha…

…racteristics, POGO parsers (#403)

* PE: Support multiple debug directories and VCFeature metadata
* Refactor `DebugData` with TE compatibility
* Add `ReproInfo` and `ExDllCharacteristicsInfo` parsers
- Added decent docs for `pe::debug` structs and constants
- Added integration tests for `pe::debug::DebugData`
* add more `IMAGE_DLLCHARACTERISTICS_EX_` fields
* Add tests for codeview/pdb70
* Add test case for binaries with no debug directories
* Add parser for `IMAGE_DEBUG_TYPE_POGO`