copies: replace _nonoverlap() by calls to manifestdict.filesnotin()
Now that we have manifestdict.filesnotin(), we can write _nonoverlap()
in terms of that method instead, enabling future speedups when
filesnotin() gets optimized, and perhaps making the code a little
clearer at the same time.
fixbundle() {
grep -v 'saving bundle' | grep -v 'saved backup' | \
grep -v added | grep -v adding | \
grep -v "unable to find 'e' for patching" | \
grep -v "e: No such file or directory"
}