NEWS:
FIXED: return code of execvp is not analysed, i.e. when running
an interpreter fails, runawk silently exits with zero exit status.
Now it fails with exit status 1 and print an error to stderr.
stdin filename defaults to "/dev/stdin"
ROOT variable in Makefile has been renamed
to more commonly used PREFIX
realloc(2) is not used anymore. arrays[ARRAY_SZ] are used now.
AWK and STDIN_FILENAME variables are removed from Makefile.
Use CPPFLAGS for changing defaults.
