Replace setup.cfg with pyproject.toml (#17)

Move the package metadata to the new format. Flake8 configuration goes
into its work file until flake8 support pyproject.toml.

.flake8

@@ -0,0 +1,28 @@
+# Configure flake8
+
+[flake8]
+max-line-length = 88
+max-doc-length = 79
+ignore =
+    # Too many leading '#' for block comment
+    E266,
+    # Line too long (82 > 79 characters)
+    E501,
+    # Do not use variables named 'I', 'O', or 'l'
+    E741,
+    # Line break before binary operator (conflicts with black)
+    W503,
+    # Ignore spaces before a colon (Black handles it)
+    E203,
+exclude =
+    .git,
+    __pycache__,
+    .ipynb_checkpoints,
+per-file-ignores =
+    # disable unused-imports errors on __init__.py
+    __init__.py: F401
+
+# Configure flake8-functions
+# --------------------------
+# Allow a max of 10 arguments per function
+max-parameters-amount = 10

pyproject.toml

@@ -1,5 +1,46 @@
-# Specify that we use setuptools and setuptools_scm (to generate the version
-# string). Actual configuration is in setup.py and setup.cfg.
+[project]
+name = "dependente"
+description = "Inspect Python package dependencies"
+dynamic = ["version"]
+authors = [
+  {name="The Dependente Developers", email="fatiandoaterra@protonmail.com"},
+]
+maintainers = [
+  {name = "Leonardo Uieda", email = "leo@uieda.com"}
+]
+readme = "README.md"
+license = {text = "MIT"}
+keywords = ["dependencies", "pyproject", "setuptools"]
+classifiers = [
+    "Development Status :: 5 - Production/Stable",
+    "License :: OSI Approved :: MIT License",
+    "Operating System :: OS Independent",
+    "Intended Audience :: Developers",
+    "Topic :: Software Development :: Libraries",
+    "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",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+]
+requires-python = ">=3.7"
+dependencies = [
+    "click>=8.0.0,<9.0.0",
+    "tomli>=1.1.0,<3.0.0",
+]
+
+[project.urls]
+"Homepage" = "https://github.com/fatiando/dependente"
+"Changelog" = "https://github.com/fatiando/dependente/blob/main/CHANGELOG.md"
+"Bug Tracker" = "https://github.com/fatiando/dependente/issues"
+"Source Code" = "https://github.com/fatiando/dependente"
+
+[project.scripts]
+dependente = "dependente.cli:main"
+
 [build-system]
 requires = ["setuptools>=45", "setuptools_scm[toml]>=6.2", "wheel"]
 build-backend = "setuptools.build_meta"