Fixed Issues in Rulex 4.3.1

The Import From Excel and Import From Text tasks did not print dedicated log messages.
This disabled root causing when internal issues affected the import process.

We have introduced several new log messages in the Import From Excel and Import From Text tasks to improve root causing.

Although workflows were computed correctly, the resulting exit code was not 0, and an incorrect error status was reported.
This behavior had no direct impact computation results or workflow execution.

This problem has now been solved.

In very uncommon situations involving nominal attributes the Join task performed incorrect memory access operations, which compromised the subsequent de-allocation at the end of the task. 

This problem has now been solved, and the task performs correctly.