pgAdmin 4 commit: Allow to generate events from the nodes, whenever som

Allow to generate events from the nodes, whenever some any events.

i.e.
'server-connect' and 'server-disconnected' events will be generated
while server gets connected and disconnected respectively.

For demo purpose - listening to the server connection from the test
script.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=5ff09223a2a8e2c63f2d5cc1bb6a9360a7cbad7a

Modified Files
--------------
.../server_groups/servers/templates/servers/servers.js      |    9 ++++++++-
web/pgadmin/browser/templates/browser/js/node.js            |    2 +-
web/pgadmin/test/static/js/test.js                          |   11 +++++++++--
3 files changed, 18 insertions(+), 4 deletions(-)