Switch to pyproject.toml + setuptools_scm

This switches to using a pyproject.toml with setuptools_scm to package
Honcho. With this configuration, MANIFEST.in is no longer needed, as
setuptools_scm automatically finds SCM-tracked package data files.

.git_archival.txt

@@ -0,0 +1,3 @@
+node: $Format:%H$
+node-date: $Format:%cI$
+describe-name: $Format:%(describe:tags=true,match=*[0-9]*)$

.gitattributes

@@ -0,0 +1 @@
+.git_archival.txt export-subst

.gitignore

@@ -7,3 +7,4 @@
 /.tox
 /build
 /dist
+/honcho/_version.py

honcho/__init__.py

@@ -1 +1,4 @@
-__version__ = '1.1.0'
+try:
+    from ._version import __version__
+except ImportError:
+    __version__ = '0.0.0+unknown'

pyproject.toml

@@ -0,0 +1,52 @@
+[build-system]
+requires = ["setuptools", "setuptools_scm[toml]"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "honcho"
+description = "Honcho: a Python clone of Foreman. For managing Procfile-based applications."
+readme = "README.rst"
+authors = [
+  {name = "Nick Stenning", email = "nick@whiteink.com"}
+]
+license.file = "LICENSE"
+keywords = ["sysadmin", "process", "procfile"]
+urls."Source" = "https://github.com/nickstenning/honcho"
+classifiers = [
+    "Environment :: Console",
+    "Intended Audience :: Developers",
+    "Intended Audience :: System Administrators",
+    "License :: OSI Approved :: MIT License",
+    "Operating System :: OS Independent",
+    "Programming Language :: Python",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.7",
+    "Programming Language :: Python :: 3.8",
+    "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
+]
+dependencies = [
+    'colorama; sys_platform=="win32"',
+]
+dynamic = ["version"]
+
+[project.optional-dependencies]
+export = ["jinja2>=3.1.2,<4"]
+docs = ["sphinx"]
+
+[project.scripts]
+honcho = "honcho.command:main"
+
+[project.entry-points.honcho_exporters]
+runit = "honcho.export.runit:Export"
+supervisord = "honcho.export.supervisord:Export"
+systemd = "honcho.export.systemd:Export"
+upstart = "honcho.export.upstart:Export"
+
+[tool.setuptools.packages.find]
+where = ["."]
+include = ["honcho*"]
+exclude = ["tests*"]
+
+[tool.setuptools_scm]
+write_to = "honcho/_version.py"