setup.py: add missing blank line.

Fix test failure in Appveyor around MSVC support

because MSVC9 may be find by new behavior at setuptools/msvc.py line 171.

Fix "failed to create process" issue on Windows

Use 'except Exception:' instead of 'except:'.

Fix continuation line unaligned for hanging indent.

Note that better would be if sdist provided some sort of hooks to better control the file copying, but since it does not, this technique will suffice for now.