Feature/msvc discovery

Tests advancement:

I tested WinSDK 7.1, WinSDK 7.0, WinSDK 6.1, VC for Python 2.7 with current arch as X86 and all possible target architecture. Environment generated from script is good for all (With some little fixes in this commit), some path are add on some case, I will look if I need to remove them. I need also to check .Net Framework 64bit in this case.

I need also to do test for sames compilers on X64 architecture, I will also test MSVC++ 2015 Build tools on X64.

I looked for create automated test on AppVeyor for this, but it is impossible to only have one of theses compilers only installed... So I did all test manually.

Feature/msvc discovery

Feature/msvc discovery

It's finished !! Now, it fully support MSVC from 9.0 to 14.0, and all theses standalone distributions:
- Microsoft Visual C++ Compiler for Python 2.7 (MSVC++9.0, x86, amd64)
- Microsoft Windows SDK 6.1 (MSVC++9.0, x86, x64, ia64)
- Microsoft Windows SDK 7.0 (MSVC++9.0, x86, x64, ia64)
- Microsoft Windows SDK 7.1 (MSVC++10.0, x86, x64, ia64)
- Microsoft Visual C++ Build Tools 2015 (MSVC++14.0, x86, x64, arm)

Next step:
- Code review.
- Test it with some MSVC versions/Architectures/Python versions combinations.

I have also some comments on the global implementation:
- I think `msvc9_find_vcvarsall` can now be deleted.
- Maybe rename the file, by example "msvc_support.py".
- Maybe Implementing it (And other distutils patchs) for not be only called by "setuptools", but also by "pkg_resources": This will automatically activate patchs for some externals packages like "Cython" transparently.

Merged in JGoutin/setuptools-1/JGoutin/first-thanks-for-the-review-this-is-very-1456944704555 (pull request #180)

feature/msvc-discovery

* Add support for MSVC11 and 12 (Only few changes with actual code needed for them).
* Python 2 compatibility for winreg.

* Rename many variable to use the same names as in MSVC .bat files. This really help to compare the Python script with original sources.
* Split compute_env to EnvironmentInfo class.
* Continue to add support for MSVC14.
* Some more little fixes.

I tested your reviewed version, and it work (Tested only on Windows x86, Python 3.4, Windows SDK 7.1 actually).

I did the following changes :

* Add many docstrings, and improve existing ones.
* Change some comments that was unclear.
* Move .NET Framework directory/version finders in "RegistryInfo", like others.
* Started to add support for the MSVC++14.0 standalone compiler. (Note that this is Work in progress). This also help me to find what fail in actual structure.
* Add "msvc9_" prefix to actual patch functions and unpatched dict for better readability.
* Add VCforPython27 alternative in _augment_exception for IA64 (Arch not supported by VCforPython27)
* Replace "lib_extra" and "sdk_extra" by more generic "ccpu_dir" and "tcpu_dir" functions (For better compatibility with MSVC++14)
* Changes some parts (like VSTools) for reduce line length, avoid repetitions and improve PEP8.
* Make "unique_everseen" and "lookup" private.


But, it is not finished, I need at least to do:

- Finish MSVC++14 support.
- Remove patch for "find_vcvarsall" for MSVC++9 ? (Now "query_vcvarsall" patch also support VC++ for Python 2.7)
- Make more tests with more compilers/platforms/Python combination.
- Check compatibility with MSVC++11 and 12.
- Rename the file in "msvc_support.py" ? (not MSVC9 only)
- Rename "RegistryInfo" ?
- Make compute_env a class ? for split subparts like you did it for "RegistryInfo" and "PlatformInfo"

Have lookup return None when it fails, moving the moving much of the try/except logic into single-line fallback expressions.

Make function private and don't use a different name for it, as it performs the same purpose. Also, it doesn't set anything.

Improve support for standalones MVC++ 9.0/10.0 compilers by setting directly the environment if Vcvarsall.bat is missing or fail.