smurf: Add a routine to expand a GRP of file system wildcards

Given a GRP that includes file system wildcards, run wordexp
and expand those wildcards, putting the result in a new GRP.
atl: Fix compiler warnings in atlDumpFits

Need to declare PAR and ERR function prototypes.
atl: Add 4th merging method

I wanted a union with priority given to the first FitsChan. This
allows me to append a second to the first with the first remaining
unchanged and only new cards being appended.