Make install-sh work even when names contain spaces or certain (but not all) shell metachars. * lib/install-sh: Remove lots of unnecessary quoting. Add double quotes where necessary. Write diagnostics to stderr, not stdout. Normalize spacing in diagnostics: use one space (not two, and not a TAB) after the leading `install:'. Remove trailing white space. Remove unnecessary curly braces. If removing the destination fails, also try to move it aside. Use `trap' more portably.