elaborate in readme

Readme.org

@@ -482,18 +482,7 @@ Note: this section only tracks the state of incomplete TODO items. Having everyt
 
 ** TODO Pre-alpha tasks
 - Shell module
-  - Only loadable via POSIX config var
+  - See todo steps in posix.rs
-  - Overload Load function to hook into this lib
-  - arg processor because these are control flow
-  - Process launching with environment variables
-  - "flag" function
-  - "switch" function
-  - "with" function (load with)
-  - Optional form of process which allows fd redirecting
-  - Background processes (bg function)
-  - Foreground process TTY (fg function)
-  - list jobs (j function)
-  - Readme documentation for POSIX module
 - logging library
 - make const all the error messages