clean up, refactor, documentation

- reducing amount of splitting in configs
- documenting configuration

vars/neovim.yml

@@ -1,8 +1,12 @@
 ---
-version: latest
+version: v0.10.3
 install_prefix: /usr/local
 install_dir: /opt/nvim
-Linux:
-  appimage:
-    dl: https://github.com/neovim/neovim/releases/latest/download/nvim.appimage
-    checksum: https://github.com/neovim/neovim/releases/download/latest/nvim.appimage.sha256sum
+use_appimage: true
+use_syspkg: true
+build_type: Release
+become: true
+git_repo: https://github.com/neovim/neovim
+appimage_url_pfx: https://github.com/neovim/neovim/releases/download
+owner: root
+group: root