FAQ.md is supposed to provide extra documentation for Rover, based on common queries from users. It's a good place to put detailed information that doesn't fit the manual. The file rover.sh has been removed and an explanation for it has been added in FAQ.md instead. The same should be done for any helper script that might become worth of mention in the future. That way we don't clutter the repository with files that aren't part of a Rover basic setup.

Makefile: add external LDFLAGS

Passing $PAGER directly as argv[0] of a subprocess only works when $PAGER is simply the name of a binary file, such as "less". Users may want to hardcode command-line options, e.g. PAGER="less -N", so we need to do something like argv = {"sh", "-c", $PAGER}. The same applies to $SHELL and $EDITOR.

Symbolic links to directories must not be followed during batch operations, otherwise we end up copying/moving/deleting the directory contents instead of the symbolic link itself.