The HLP-changes to sbase have been a great addition of functionality,
but they kind of "polluted" the enmasse() and recurse() prototypes.
As this will come in handy in the future, knowing at which "depth"
you are inside a recursing function is an important functionality.
Instead of having a special HLP-flag passed to enmasse, each sub-
function needs to provide it on its own and can calculate results
based on the current depth (for instance, 'H' implies 'P' at
depth > 0).
A special case is recurse(), because it actually depends on the
follow-type. A new flag "recurse_follow" brings consistency into
what used to be spread across different naming conventions (fflag,
HLP_flag, ...).
This also fixes numerous bugs with the behaviour of HLP in the
tools using it.
The -d option is a GNU extension and is equivalent to its "-P
--preserve=links" options.
Since we don't implement the --preserve=links functionality anyway (it
means preserve hard links between files), just call it -P, which is
specified by POSIX.
Additionally, there is no need to check for cp_Pflag again before
copying the symlink itself because the only way the mode in the stat
will indicate a symlink is if we used lstat (which we only do if -P is
specified).
