Update docs for release to 0.15.5.0 and other updates. (#469)

* Replace reference to .travis with .github/workflows/...
* Update where version info is stored in src/.
* Release procedure updates.

Author: itsayellow

docs/changelog.md

@@ -1,7 +1,7 @@
-dev
+0.15.5.0
 - pipx now parses package specification before install.   It removes (with warning) the `--editable` install option for any package specification that is not a local path.   It also removes (with warning) any environment markers.
 - Disabled animation when we cannot determine terminal size or if the number of columns is too small. (Fixes #444)
-- Version of each injected package is now listed after name for `pipx list --include-injected`
+- [feature] Version of each injected package is now listed after name for `pipx list --include-injected`
 - Change metadata recorded from version-specified install to allow upgrades in future.  Adds pipx dependency on `packaging` package.
 - [bugfix] Prevent python error in case where package has no pipx metadata and advise user how to fix.
 - [feature] `ensurepath` now also ensures that pip user binary path containing pipx itself is in user's PATH if pipx was installed using `pip install --user`.

docs/contributing.md

@@ -75,7 +75,7 @@ nox -s lint
 ```
 
 ## Testing pipx on Continuous Integration builds
-When you push a new git branch, tests will automatically be run against your code as defined in `.travis`.
+When you push a new git branch, tests will automatically be run against your code as defined in `.github/workflows/on-push.yml`.
 
 ## Building Documentation
 
@@ -103,8 +103,10 @@ nox -s publish_docs
 ## Releasing New `pipx` Versions
 To create a new release
 
-* update pipx's version in `main.py` and regenerate documentation
-* make sure the changelog is updated
+* Update pipx's version in `src/pipx/version.py` and regenerate documentation.
+* Make sure the changelog is updated
+  * Add new version to head the latest block of changes (instead of "dev").
+  * Make sure all notable changes are listed.
 
 Finally, run
 ```bash