ipaplatform: Link to platform module during build time

https://fedorahosted.org/freeipa/ticket/4052

Reviewed-By: Petr Viktorin <pviktori@redhat.com>

.gitignore

@@ -68,6 +68,10 @@ freeipa2-dev-doc
 
 /ipapython/setup.py
 /ipapython/version.py
-/ipapython/services.py
 !/ipapython/Makefile
 !/ipapython/py_default_encoding/Makefile
+
+/ipaplatform/setup.py
+/ipaplatform/tasks.py
+/ipaplatform/services.py
+/ipaplatform/paths.py