add reverse, snippet for prepend implementation

Readme.org

@@ -312,14 +312,6 @@ Will need a concatenate function for tables
 *** TODO Main shell calls Load function on arg and exits
 *** TODO Can enter multiple lines of text, with formatting in repl
 *** TODO append -> cons
-*** TODO string operations
-**** DONE typecast (string)
-**** DONE contains
-**** DONE strlen
-**** DONE concat
-**** TODO substr by index
-**** TODO split (on delimiter)
-**** TODO strcons (sprintf but its all string tokens under the hood)
 *** TODO Shell module
 **** TODO Support for single quoting string literals
 **** TODO Args parsing helper
@@ -328,23 +320,6 @@ Will need a concatenate function for tables
 **** TODO Foreground process TTY
 **** TODO Background processes
 **** TODO Update config env var docstring with functions loaded or unloaded
-*** TODO list operations
-**** DONE append
-**** TODO head (returns (head rest))
-***** TODO let destructuring test
-**** TODO tail (returns (rest tail))
-***** TODO let destructuring test
-**** TODO queue (append to front)
-**** TODO snippet for dequeue
-**** TODO snippet for pop
-**** TODO sublist by delimiter
-**** DONE front (returns copy of first elem)
-***** DONE normal positive test
-***** DONE test for err case on empty list
-**** DONE back (returns copy of last elem)
-***** DONE normal positive test
-***** DONE test for errcase on empty list
-**** DONE list len
 *** TODO lambda
 *** TODO bool cast
 *** TODO file operations