Build system tidying

This should hopefully fix up some warnings and improve the contents of
the sdist tarball -- we were including `docs/_build`.

MANIFEST.in

@@ -23,10 +23,7 @@ graft pywwt/web_static
 
 # Documentation
 graft docs
-exclude docs/\#*
-prune docs/build
-prune docs/gh-pages
-prune docs/dist
+prune docs/_build
 
 # Tests
 graft tests

setup.cfg

@@ -1,3 +1,3 @@
 [metadata]
 name = pywwt
-description-file = README.rst
+description_file = README.rst

setup.py

@@ -85,7 +85,7 @@ setup_args = dict(
     long_description_content_type="text/markdown",
     version=version,
     cmdclass=cmdclass,
-    packages=find_packages(),
+    packages=find_packages("pywwt"),
     author="WorldWide Telescope team",
     author_email="hello@worldwidetelescope.org",
     url="https://github.com/WorldWideTelescope/pywwt",

setupbase.py

@@ -102,11 +102,7 @@ def find_packages(top=HERE):
     """
     packages = []
     for d, dirs, _ in os.walk(top, followlinks=True):
-        if os.path.exists(pjoin(d, "__init__.py")):
-            packages.append(os.path.relpath(d, top).replace(os.path.sep, "."))
-        elif d != top:
-            # Do not look for packages in subfolders if current is not a package
-            dirs[:] = []
+        packages.append(os.path.relpath(d, HERE).replace(os.path.sep, "."))
     return packages