add "python" option to zope.conf schema allowing for a python binary to be...

add "python" option to zope.conf schema allowing for a python binary to be specified, allowed a Zope instance to run from any buildout with the appropriate eggs.

src/Zope2/Startup/zopectl.py

@@ -129,7 +129,7 @@ class ZopeCtlOptions(ZDOptions):
             self.sockname = config.runner.socket_name
         else:
             self.sockname = os.path.join(self.clienthome, "zopectlsock")
-        self.python = sys.executable
+        self.python = config.python or sys.executable
         self.zdrun = os.path.join(os.path.dirname(zdaemon.__file__),
                                   "zdrun.py")
         if WIN:

src/Zope2/Startup/zopeschema.xml

@@ -945,4 +945,14 @@
    </description>
   </multisection>
 
+    <key name="python" datatype="existing-path"
+         required="no">
+      <description>
+        Path to the Python interpreter for use by zdaemon.
+        Defaults to sys.executable.
+        Needed for buildout-based instances to supply a python
+        that has all the correct eggs on the path.
+      </description>
+    </key>
+
 </schema>