Creates a URI for use with QgsVectorLayerExporter corresponding to given destination
table options for the backend. The URI format and extra options which
need to be passed to QgsVectorLayerExporter differ from provider to
provider, so this new method gives us a consistent, generic method we
can call to safely generate the right URI and options in a
cross-provider way.
Implemented for all database connection providers.
sip6 converts all enums to python Enums, but ONLY creates
Enums with IntFlags types when the c++ type is an enum class : int.
Accordingly we need to patch back in all the operations which treat
enum values as ints, like |, &, bool, etc.
The long term solution here is to move all our c++ enums to enum
class, but that's not always straightforward and can break API
for plugins if it involves the signature of virtual methods.
