conda build alternatives for Windows?
`conda` has been the widely suggested method for building / developing `pandas` on Windows.  However, given that upstream libraries like `numpy` and `scipy` are in the process / can be supported with many other build environments on Windows, it seems natural that `pandas` should support alternative build environments given that its build requirements are much more lenient (just need a C compiler) compared to those of `numpy` and `scipy`.  Some major alternatives are:

1) `mingw-w64`
2) `Cygwin`

Initial testing with the second one are promising and suggest that `pandas` can already support it.  The former has not been tested yet but should work in theory given that it works with `numpy` for example.
