Added merger of cursors and of duplicates. IntoIterator implementations
for Cursors which maintain a local copy of the value modified to use
take() instead of .clone()ing values. Getting closer to zero copy.
Merger uses Ord wrappers on the cursors themselves to provide duplicate
sorting or unsorting, which removes the need to copy values to wrap them
in an ordering wrapper.
Overall, code is getting simpler with fewer copies, a win-win.
projects / mtbl-rs / commit