python goes superenv
python goes superenv

- Install a sitecustomize.py that is only executed for brewed
  python to
  -  Fix the prefix, python thinks it is installed to.
     (Remember, Python thinks it lives in the Cellar)
  -  Remove "/System/..." stuff from sys.path which caused
     a lot of install trouble because setuptools has the
     habbit to inject itself upfront, overwriting our distribute.
- Allow --with-poll and don't say, we didn't warn you.
- Don't need depends_on :x11 any longer. Yeah, no XQuartz!
- Add --with-brewed-openssl
- pip 1.2.1
- pip, pip-2.7, easy_install and easy_install-2.7 are installed
  to prefix, such that they are directly available, even if
  people have not set their PATH to include
  $(brew --prefix)/share/python
- Caveats shorter and clear.
- For Xcode-only:
  - Patch the distutils buildsystem to use "xcrun cc" etc.
  - Teach distutils the MacOS.sdk_path (for incs and libs)
- superenv.rb add the right python include dir depending on
  whether a brewed python is installed or not.

Closes Homebrew/homebrew#15064.

Signed-off-by: Max Howell <6ab8060e002788ba9309d53dba8df070e650cb04@me.com>
ilovezfs/homebrew-core,FinalDes/homebrew-core,grhawk/homebrew-core,bigbes/homebrew-core,kuahyeow/homebrew-core,mvitz/homebrew-core,tkoenig/homebrew-core,forevergenin/homebrew-core,gserra-olx/homebrew-core,j-bennet/homebrew-core,aabdnn/homebrew-core,moderndeveloperllc/homebrew-core,jabenninghoff/homebrew-core,passerbyid/homebrew-core,mvbattista/homebrew-core,cblecker/homebrew-core,dsXLII/homebrew-core,lembacon/homebrew-core,filcab/homebrew-core,mbcoguno/homebrew-core,chrisfinazzo/homebrew-core,wolffaxn/homebrew-core,makigumo/homebrew-core,git-lfs/homebrew-core,j-bennet/homebrew-core,nandub/homebrew-core,smessmer/homebrew-core,Homebrew/homebrew-core,bigbes/homebrew-core,fvioz/homebrew-core,aabdnn/homebrew-core,wolffaxn/homebrew-core,gserra-olx/homebrew-core,DomT4/homebrew-core,BrewTestBot/homebrew-core,lemzwerg/homebrew-core,wolffaxn/homebrew-core,mvbattista/homebrew-core,adamliter/homebrew-core,mfikes/homebrew-core,jdubois/homebrew-core,reelsense/homebrew-core,DomT4/homebrew-core,stgraber/homebrew-core,mvitz/homebrew-core,git-lfs/homebrew-core,smessmer/homebrew-core,jvehent/homebrew-core,jdubois/homebrew-core,edporras/homebrew-core,mbcoguno/homebrew-core,bcg62/homebrew-core,bfontaine/homebrew-core,mahori/homebrew-core,LinuxbrewTestBot/homebrew-core,maxim-belkin/homebrew-core,sjackman/homebrew-core,FinalDes/homebrew-core,andyjeffries/homebrew-core,Moisan/homebrew-core,battlemidget/homebrew-core,stgraber/homebrew-core,nbari/homebrew-core,forevergenin/homebrew-core,Moisan/homebrew-core,cblecker/homebrew-core,aren55555/homebrew-core,jvehent/homebrew-core,Linuxbrew/homebrew-core,sjackman/homebrew-core,phusion/homebrew-core,JCount/homebrew-core,jabenninghoff/homebrew-core,nbari/homebrew-core,spaam/homebrew-core,LinuxbrewTestBot/homebrew-core,zyedidia/homebrew-core,lembacon/homebrew-core,kunickiaj/homebrew-core,adam-moss/homebrew-core,Linuxbrew/homebrew-core,rwhogg/homebrew-core,lembacon/homebrew-core,fvioz/homebrew-core,tkoenig/homebrew-core,zmwangx/homebrew-core,mbcoguno/homebrew-core,lasote/homebrew-core,zmwangx/homebrew-core,sdorra/homebrew-core,jvillard/homebrew-core,jdubois/homebrew-core,bfontaine/homebrew-core,Homebrew/homebrew-core,bcg62/homebrew-core,battlemidget/homebrew-core,JCount/homebrew-core,reelsense/homebrew-core,moderndeveloperllc/homebrew-core,spaam/homebrew-core,ShivaHuang/homebrew-core,passerbyid/homebrew-core,ShivaHuang/homebrew-core,kuahyeow/homebrew-core,bcg62/homebrew-core,adam-moss/homebrew-core,grhawk/homebrew-core,edporras/homebrew-core,straxhaber/homebrew-core,sdorra/homebrew-core,uyjulian/homebrew-core,andyjeffries/homebrew-core,zyedidia/homebrew-core,aren55555/homebrew-core,makigumo/homebrew-core,mahori/homebrew-core,robohack/homebrew-core,lasote/homebrew-core,mfikes/homebrew-core,ylluminarious/homebrew-core,ylluminarious/homebrew-core,adamliter/homebrew-core,jvillard/homebrew-core,lemzwerg/homebrew-core,uyjulian/homebrew-core,dsXLII/homebrew-core,mvitz/homebrew-core,ilovezfs/homebrew-core,kunickiaj/homebrew-core,maxim-belkin/homebrew-core,straxhaber/homebrew-core,phusion/homebrew-core,robohack/homebrew-core,nandub/homebrew-core,chrisfinazzo/homebrew-core,rwhogg/homebrew-core,jvillard/homebrew-core,BrewTestBot/homebrew-core,filcab/homebrew-core