[Cython] Standard include path

[Stefan Behnel]

Stefan Behnel wrote:
> Dag Sverre Seljebotn wrote:
>> There are two ways of going about this:
>> - Have runtests.py always include the Includes dir
>> - Have Cython itself always include the Includes dir (i.e. always
>> ../../Includes relative to Cython/Compiler/Main.py).
>>
>> I prefer the latter one; thoughts?
> 
> I'm fine with the second one as long as it goes last on the include path, so
> that people can override it.
> 
>> I suppose this might also mean 
>> installing Includes "somewhere" on setup.py (or is that already done?)
> 
> It should go into the "package_data" setup. Note sure where it should be
> installed, but Cython/Includes sounds good to me (i.e. package data of the
> "Cython" package).

I changed the setup.py to install it as Cython/Includes. It's not used as
import path yet, but that should be trivial.

Stefan