Rename custom scripts for `plugin-add` and `plugin-remove` phases in plugins to make clear when they are executed:
`plugin-add` -> `post-plugin-add`
`plugin-remove` -> `pre-plugin-remove`
Previously, if we ran a command like `asdf install` and we encountered a
plugin that didn't exist, asdf produces an error saying "No such
plugin". Without knowing which plugin it could be referring too, we'd
have to manually go through each plugin in `.tool-versions` to find the
culprit.
With this commit, we'll now also include the plugin name as part of the
messaging for easier debugging.
- Remove plugin shims when last version is uninstalled.
- Remove shims on plugin-remove
When the latest version of a tool is uninstalled,
Remove the plugin shims (marked with metadata at #122)
Also found lots of missing tests and added them.
Closes#67