* Rename `versions.Installed` function to `IsInstalled`
* Create `versions.Installed` function
* Create `shims.GenerateForPluginVersions` and `shims.GenerateAll` functions
* Address linter warnings
* Create asdf reshim command
* Run asdf hook from new `shims` functions
* Add `x/sys` as a dependency
* Create `toolversions.Unique` function
* Create `shims` package with `ExecutablePaths`, `PluginExecutables`, `Write`, `GenerateForVersion` function
* Address linter warnings
* Get asdf info BATS tests working
* Create `versions.Installed` function
* Update `versions.Latest` to return single version
* Implement `latest` asdf command
* Refactor config package so default settings are always used with config file not loaded
* Update `findVersionsInDir` to check legacy files
* Refactor functions in internal/resolve package to return `ToolVersion` structs instead of version slices
* Refactor `findVersionsInEnv` function to return env variable name
* Create `resolve.Version` function
Some of the Go tests actually cloned remote repos, which meant slow tests, and tests failures if I was working offline. These changes allow all Go tests to run offline. The test code now clones local Git repos instead of remotes ones.
* Add otiai10/copy as a dependency
* Create repotest package for test code that needs to work with Git repos
* Add back missing test script for execute package
* Update git, pluginindex, and plugins package tests so they work offline
* Implement info command
* Remove duplicate and unneeded BATS tests from `main_test.go`
* remove download dir for plugin when removing plugin
* update plugins.Add function so downloads directory is created
* Create `plugins.New` function, updating existing code to use it
* Add another test for `hook.Run` function
* Enable `plugin_add_command.bats` tests for Go implementation of asdf
* Add `RunCallback` method to `Plugin` struct
* Update `plugins.Add` function to run `post-plugin-add` plugin callback script
* Handle Bash expression and scripts properly in `execute` package so `$@` is always set
* Create `pluginindex.Build` function
* Use `pluginindex` when no plugin URL provided for plugin add command
* Get more `plugin_add_command` BATS tests passing against Golang version
* Only use `pluginindex` when it is not disabled
* Update error message so it matches legacy format
* Add staticcheck.conf
* Move plugins/git package to /git.
* Update repoer interface in pluginindex package to match interface in git package
* Use git package's Repo struct in pluginindex package
* Switch to non-verbose test output in Makefile
* Create pluginindex package with PluginIndex struct with methods for updating index and retrieving plugin URLs
* Create IndexRepo interface to allow for easy testing out cloning real Git repository.
* Simplify BATS test Golang code
* Update plugin add test to new command format
* Correctly set `ASDF_DATA_DIR` for BATS tests
* Rename `PluginAdd` function to `Add`
* Create `plugin.Remove` function
* Make plugin remove command invoke `plugin.Remove` function
