django1: Add python3-django1 package

This adds a Python 3 version of the django1 package.

This also adds a python-django1-common package that contains a
django-admin script based on the one in Debian[1]. This allows
python-django1 and python3-django1 to be installed at the same time.

python3-django conflicts with python-django1 (via python-django1-common)
and python3-django1.

This also updates older Python 3 Django plugin packages to depend on
python3-django1, and newer plugin packages to depend on "django", which
both python3-django and python3-django1 provide.

Because of this dependency on either version of Django, the MDEPENDS for
Python 3 Django plugin packages no longer functions correctly and has
been removed.

[1]: https://salsa.debian.org/python-team/modules/python-django/blob/debian/buster/debian/django-admin

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

lang/python/django-formtools/Makefile

@@ -7,7 +7,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=django-formtools
 PKG_VERSION:=2.1
-PKG_RELEASE:=6
+PKG_RELEASE:=7
 
 PYPI_NAME:=$(PKG_NAME)
 PKG_HASH:=7703793f1675aa6e871f9fed147e8563816d7a5b9affdc5e3459899596217f7c
@@ -47,9 +47,8 @@ define Package/python3-django-formtools
 $(call Package/django-formtools/Default)
   DEPENDS:= \
 	+PACKAGE_python3-django-formtools:python3 \
-	python3-django
+	+PACKAGE_python3-django-formtools:python3-django1
   VARIANT:=python3
-  MDEPENDS:=python3-django
 endef
 
 define Package/python3-django-formtools/description