Add prototype of assert_script
Second prototype of assert_script

Handle output that does not end with a newline.  Convert to using env in expect
script.
Add prototype for expect script runner

Scaffolds the script to run the script defined by assert_script.  To use this
script, split along each ps boundary and escape '{}\' in the strings (see
http://stackoverflow.com/questions/5302120/general-string-quoting-for-tcl).
Add support for re spans to script prototype
Grumble work on expect script
Continued work on expect prototype
some more prototype notes
Continued work, looking at some exceptional cases