Start slon passing with a slon configuration file

Implement a new parameter on node configuration to allow to specify
a slon configuration file to be used to start the slon daemon

adjusted slon_start and get_pid functions to consider the new start string

Branch
------
master

Details
-------
http://git.postgresql.org/gitweb?p=slony1-engine.git;a=commitdiff;h=ddfd1c4ea9bc4b5a5043bb1d126bc6c65d825173

Modified Files
--------------
tools/altperl/slon-tools.pm          |   27 ++++++++++++++++++++++-----
tools/altperl/slon_tools.conf-sample |   14 +++++++++-----
2 files changed, 31 insertions(+), 10 deletions(-)