* Moves multi reader initialization
* Log error message if not able to open file
* Make keywordCount pure virtual
The base class `RifSummaryReaderInterface` is changed to be abstract and the `keywordCount` is declared as a pure virtual method, therefore the derived classes must implement the method.
This will ensure that all readers are responsible for reporting a keyword count.
* Ensures addresses are created if required
Calls `createAddressesIfRequired` on the summary reader to ensure addresses are created before accessing keyword count.
This prevents potential issues when the addresses haven't been initialized yet.
* Support cross plot in plot templates
* Fix source stepping for cross plots
* Show cross plot data in "Show Plot Data"
* Use bin size and realization count when computing cross plot statistics
* Remove use of RifEnsembleStatisticsReader
* Add RimSummaryAddressSelector and RimEnsembleCrossPlotStatisticsCase
* Remove RifEnsembleStatisticsReader
* Add support for cross plot x-axis selection
* Support source stepping on ensemble cross plot curves
* Add isXAxisSummaryVector
Magne Sjaastad
Kristian Bendiksen