add TODO

TODO.md

@@ -0,0 +1,37 @@
+# TODO
+### @ version: 0.1.0-beta
+
+<!-- these are things to be done in the project
+to be struck/checked off as completed incl. commit ID
+and archived under (completed) before next version
+the remainder at a version is rolled over to the next
+    unless the item is dismissed altogether -->
+
+### code
+- [ ] add `set -e` for entire script escaped by `set +e` where needed
+    - pointed out by @iammosespaulr
+
+### documentation
+- [ ] `-d` has incorrect info
+    - default is src dir
+- [ ] `-h` and `-v` are not mentioned
+- [ ] formatting needs work
+- [ ] lightweight copy needs explanation
+
+### functionality
+- [ ] heavily dependent on GNU coreutils - `realpath`
+    - unsatisfied dependency to be handled
+- [ ] clone would overwrite existing .bak/.old
+    - plan to rename existing file with ctime in suffix
+- [ ] installation/uninstallation/update capabilities pending
+
+### miscellaneous
+- [ ] to decide and add license for RC
+    - include in script keeping with zero-conf, single-file idea?
+
+### completed
+<!-- template START \
+<details>
+<summary>@ vN.N.N-xxx</summary>
+</details>
+     template END -->