Centralize Abstract{Input,Output}StatementSupport.parseArgumentValue()

Centralize Abstract{Input,Output}StatementSupport.parseArgumentValue()

As we have reduced the number of implementations of this method,
by introducing the default implementation, we are down to three
possible implementations under BaseSchemaTreeStatementSupport.

Add a level of indirection through Function<QNameModule, QName>, which
allows us to combine the two implementations into a single one residing
in BaseOperationContainerStatementSupport.

Change-Id: Ia5232d356ce2141800a950e6222cdc2174cd926b
Signed-off-by: Robert Varga <robert.varga@pantheon.tech>