More .gitignore adjustments to cope with NFS hidden files.
Pseudo-code for new symbols.c that handles builtins.
Unterminated macro.
Other brief changes? Switching branches.
Some consistency and typo fix
More prototype code.  Things have gotten busy and there hasn't been a
commit for a while.  Here is the prototype code for the WORD builtin
which does work correctly.  I need to refine the interface in calling
back into Resolve_Symbol and updating the output.  I will examine the
apply_* functions for the ':' and '::' syntax for inspiration.
Added code for WORDS builtin.
Tweak some comments.
Added code to support the ORIGIN builtin.
Almost working builtins.  Currently no support for calls that process
their own arguments, but getting much closer.
Switching branches...
Handle unrecognised functions, as well as builtins that return
an empty string.
Support for ERROR, INFO, WARN builtin functions.
Allow lines of zero length in the parse tables.  Sometimes Resolve_Symbol
might return a line of zero length to Parse_Descrip and this is not an
error.
Minor clean up.
Switching branches...
Added WORDLIST builtin.  Also improved the cat() function to handle
contactenating multiple string/length pairs to an existing string.
Updated documentation for cat so it is a bit clearer exactly what this
function can do.
Improve range checking in WORD and WORDS in line with WORDLIST.
Add FIRSTWORD and LASTWORD.