add remove

src/action.rs

@@ -2,6 +2,7 @@ pub(crate) const CLEAN: &str = "clean";
 pub(crate) const EDIT: &str = "edit";
 pub(crate) const GROUPS: &str = "groups";
 pub(crate) const IMPORT: &str = "import";
+pub(crate) const REMOVE: &str = "remove";
 pub(crate) const SHOW: &str = "show";
 pub(crate) const SYNC: &str = "sync";
 pub(crate) const UNMANAGED: &str = "unmanaged";