make defCountHit protected. update comment
add "hard" option that emulates unix hard links vs current "soft" behavior
also make some private fields protected to allow subclassing (in testing)
add "once" and "mapTo" options
"once" complements "create" by terminating processing if a node already exists
"mapTo" augments auto-iteration over maps (akin to arrays) by exporting key values
getFilteredValue helper method added for subclasses
tree node initializer fixes

removed tree node initializer interface from all tree node implementations. They were
all no-ops, and no different from simply passing in a null creator parameter. Reduces
method/interface clutter on nodes (they could really use it), and erroneous results
for searches of actual implementers.
new nodes with an alias config reported as new

previously the aliasTo node initializer would pre-empt the logic
that supports the isnew flag. This would prevent parent nodes from
being updated accordingly. Since the alias contract mostly has to
do with interactions with child nodes, and explicitly does not
share meta data on the alias'd node itself, it is unintuitive for
it to not update parent nodes' data attachments and creates an
inconsistency between eg. the parent's count of child nodes and
how its data attachments are supposed to behave that we could
otherwise rely on.

Since I believe this removes the need to check the hits counter on
newly created child nodes for the once flag, that check has also
been removed.
Merge pull request #11 from stewartoallen/4pull-path-updates

4pull path updates