sh: Simplify list() in the parser.
sh: Simplify list() in the parser.

The erflag argument was only used by old-style (``) command substitutions.
We can remove it and handle the special case in the command substitution
code.

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase