Logging PDF generation on Linux systems

Starting from Patch 1, the log file changes from /var/log/BESWebReportsPdfExport.log into /var/log/BESWebReports/PdfExport.log

The /var/opt/BESWebReportsServer/BESReportsData/BESExe/generatepdf.sh script, by default, redirects only the stdout to the log file.

To redirect also the stderr to the log file, modify the generatepdf.sh script as follows:

redirect_stderr=1