python packages: move all things python under lang/python

I admit this may be be a bit aggressive, but the lang
folder is getting cluttered/filled up with Python, PHP, Perl,
Ruby, etc. packages.

Makes sense to try to group them into per-lang folders.

I took the Pythons.

Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>

lang/python/python3/files/python3-version.mk

@@ -0,0 +1,17 @@
+#
+# Copyright (C) 2007-2016 OpenWrt.org
+#
+# This is free software, licensed under the GNU General Public License v2.
+# See /LICENSE for more information.
+#
+
+# Note: keep in sync with setuptools & pip
+PYTHON3_VERSION_MAJOR:=3
+PYTHON3_VERSION_MINOR:=6
+PYTHON3_VERSION_MICRO:=1
+
+PYTHON3_VERSION:=$(PYTHON3_VERSION_MAJOR).$(PYTHON3_VERSION_MINOR)
+
+PYTHON3_SETUPTOOLS_VERSION:=28.8.0
+PYTHON3_PIP_VERSION:=9.0.1
+