bug 322 allow CLONE PREPARE processing to deal with an earlier STORE PATH

If a node sees a STORE PATH  event before it sees the CLONE PREPARE
that creates a node involved in that path then the CLONE PREPARE
event was failing because the node was already in sl_node.

Check for the existance for rows and update them instead

Conflicts:
	src/slon/remote_worker.c

Branch
------
REL_2_2_STABLE

Details
-------
http://git.postgresql.org/gitweb?p=slony1-engine.git;a=commitdiff;h=393dc4330cc2028fbfa9fdc0a16be960001f9918

Modified Files
--------------
src/backend/slony1_funcs.sql |   30 +++++++++++++++++++++++++-----
1 file changed, 25 insertions(+), 5 deletions(-)