WLS_Datasource Fixes and Enhancements

Hi Edwin,

Here are a couple of changes to the wls_datasource type:

1. Added FAN Enabled flag and ONS Node List parameter to enable creation of Gridlink datasources

2. Updated modify action to remove existing extraproperties from the datasource before considering the extraproperties value. This fixes a problem where an extraproperty can be defined during create, then removed from the Puppet config yet it still persists in the WL config.

I added a conditional to avoid removing the "user" property during this purge of extraproperties.

Let me know if you find any issues.

Cheers,
Brad