Update after PR comments

MANIFEST.in

@@ -1,5 +1,2 @@
-include CHANGELOG.md
-include CONTRIBUTING.md
-include README.md
 include requirements.txt
 include LICENSE

README.release.md

@@ -6,7 +6,7 @@
 - Update the release history in `CHANGELOG.md`:
   - Change "Unreleased" to the current release version and date.
   - Create empty "Unreleased" section.
-  - Add proper link to the new release (at the bottom of the file).
+  - Add proper link to the new release (at the bottom of the file). Use GitHub [compare feature](https://docs.github.com/en/free-pro-team@latest/github/committing-changes-to-your-project/comparing-commits#comparing-tags) between two tags.
   - Update "Unreleased" link (at the bottom of the file).
 - Run linters and tests:
   - `export B2_TEST_APPLICATION_KEY=your_app_key`
@@ -17,12 +17,13 @@
 - Commit and push to GitHub, then wait for CI workflow to complete successfully.
   - No need to make a branch. Push straight to `master`.
 - Tag in git and push tag to origin.  (Version tags look like "v0.4.6".)
-    - `git tag vx.x.x`
-    - `git push origin vx.x.x`
+  - `git tag vx.x.x`
+  - `git push origin vx.x.x`
 - Wait for CD workflow to complete successfully.
   - Verify that the GitHub release is created
   - Verify that the release has been uploaded to the PyPI
-- Install using pip and verify that it gets the correct version.
+- Install using pip and verify that it gets the correct version:
+  - `pip install -U b2sdk`
 - Update for dev:
   - Bump the version number to an odd number (for example: 1.0.2 -> 1.0.3)
   - Commit the changes and push to GitHub again.

setup.py

@@ -117,9 +117,7 @@
 
     # If there are data files included in your packages that need to be
     # installed, specify them here.
-    package_data={
-        'b2sdk': ['CHANGELOG.md', 'CONTRIBUTING.md', 'README.md', 'requirements.txt', 'LICENSE']
-    },
+    package_data={'b2sdk': ['requirements.txt', 'LICENSE']},
 
     # Although 'package_data' is the preferred approach, in some case you may
     # need to place data files outside of your packages. See: