Python: remove pythonSmall

In #19309 a separate output for tkinter was added.

Several dependencies of Python depend indirectly on Python. We have the
following two paths:
```
‘python-2.7.12’ - ‘tk-8.6.6’ - ‘libXft-2.3.2’ - ‘libXrender-0.9.10’ -
‘libX11-1.6.4’ - ‘libxcb-1.12’ - ‘libxslt-1.1.29’- ‘libxml2-2.9.4’ -
‘python-2.7.12’

‘python-2.7.12’ - ‘tk-8.6.6’ - ‘libXft-2.3.2’ - ‘fontconfig-2.12.1’ -
‘dejavu-fonts-2.37’ - ‘fontforge-20160404’ - ‘python-2.7.12’
```
Because only `tkinter` needs this, I added
```
pythonSmall = python.override {x11Support = false;};
```
to break the infinite recursion. We also still have the output
`tkinter`.

However, we might as well build without x11Support by default. Then we build with x11Support as well so we get the tkinter module and put that in a separate package.

pkgs/development/interpreters/python/cpython/3.4/default.nix

@@ -6,7 +6,7 @@
 , openssl
 , readline
 , sqlite
-, tcl ? null, tk ? null, libX11 ? null, xproto ? null, x11Support ? !stdenv.isCygwin
+, tcl ? null, tk ? null, libX11 ? null, xproto ? null, x11Support ? false
 , zlib
 , callPackage
 , self
@@ -101,14 +101,8 @@ in stdenv.mkDerivation {
     # FIXME: should regenerate this.
     rm $out/lib/python${majorVersion}/__pycache__/_sysconfigdata.cpython*
 
-  '' + optionalString x11Support ''
-    # tkinter goes in a separate output
-    mkdir -p $tkinter/${sitePackages}
-    mv $out/lib/${libPrefix}/lib-dynload/_tkinter* $tkinter/${sitePackages}/
   '';
 
-  outputs = ["out"] ++ optional x11Support "tkinter";
-
   passthru = rec {
     inherit libPrefix sitePackages x11Support;
     executable = "${libPrefix}m";