(env): add pyproject.toml w/ poetry build-system

- use poetry primarily for dependency management moving forward
  - would also like to use for simplifying packaging as well in the
    future

- add most of everything from MANIFEST.in, setup.cfg, and setup.py
  into poetry sections
  - TODO: remove MANIFEST.in, setup.cfg, setup.py etc once the builds
    are completely equivalent
    - currently doesn't build a (dated) egg, has less keywords, and
      custom URLs may not work in this version (needs a 1.0.0
      prerelease probably)
      - setup.py in tarball is missing a lot, including classifiers,
        long_description_content_type, keywords, project_urls, and
        is using distutils instead of setuptools
        - think most are fixed in the 1.0.0 prereleases
      - tarball is also missing egg-info
        - unsupported by poetry and probably unnecessary anyway tbh,
          not sure if any users used eggs
      - PKG-INFO has keywords comma separated instead of space
        separated as the setup.py (i.e. non-poetry) does

pyproject.toml

@@ -0,0 +1,73 @@
+[tool.poetry]
+name = "django-serializable-model"
+version = "0.0.5"
+description = "Django classes to make your models, managers, and querysets serializable, with built-in support for related objects in ~100 LoC"
+readme = "README.md"
+
+packages = [
+    { include = "django_serializable_model.py" },
+    # this is the original, unintended name, and should be removed in the
+    # first breaking/major release, v1.0.0. See `serializable.py` comment.
+    { include = "serializable.py" }
+]
+include = [
+    "LICENSE",
+    "CHANGELOG.md"
+]
+
+authors = ["Anton Gilgur"]
+license = "Apache-2.0"
+homepage = "https://github.com/agilgur5/django-serializable-model"
+repository = "https://github.com/agilgur5/django-serializable-model"
+documentation = "https://github.com/agilgur5/django-serializable-model"
+
+classifiers=[
+    "Natural Language :: English",
+    "Intended Audience :: Developers",
+    "Topic :: Software Development :: Libraries",
+    "License :: OSI Approved :: Apache Software License",
+
+    "Development Status :: 3 - Alpha",
+    "Operating System :: OS Independent",
+    "Programming Language :: Python :: 2",
+    "Programming Language :: Python :: 2.7",
+    "Programming Language :: Python :: 3",
+    "Framework :: Django",
+    "Framework :: Django :: 1.4",
+    "Framework :: Django :: 1.5",
+    "Framework :: Django :: 1.6",
+    "Framework :: Django :: 1.7",
+    "Framework :: Django :: 1.8",
+    "Framework :: Django :: 1.9",
+    "Framework :: Django :: 1.10",
+    "Framework :: Django :: 1.11",
+    "Framework :: Django :: 2.0",
+    "Framework :: Django :: 2.1",
+    "Framework :: Django :: 2.2"
+]
+keywords=[
+    "django",
+    "serializer",
+    "serializers",
+    "serializer-django",
+    "serialize",
+    "json",
+    "dict",
+    "queryset",
+    "model",
+    "modelmanager",
+    "full",
+    "wadofstuff"
+]
+
+[tool.poetry.urls]
+"Tracker" = "https://github.com/agilgur5/django-serializable-model/issues"
+
+[tool.poetry.dependencies]
+python = "^2.7 || ^3"
+
+[tool.poetry.dev-dependencies]
+
+[build-system]
+requires = ["poetry>=0.12"]
+build-backend = "poetry.masonry.api"