don't use global cfile at all but only an untpyed handle to call the cf_... functions in file.c
move the save_file member from capture_file to capture_opts, as it's only used while capturing and while preparing it
svn path=/trunk/; revision=13276
Hopefully the unspecified forward declaration of capture_options_t in main.h is portable, but buildbot will tell me. This way I need the internals of that struct only at the places I really use it.
svn path=/trunk/; revision=12853