Create function to save tables in csv files in reporting directory

[malexan]

Currently I use write.csv, but the function should be more general. For example users will decide reports to be written in SQL data base. In this case we will need to change only one function definition instead of replacing write.csv across the whole module code.

It takes only name of data set as parameter. reportdir could be optional or be taken from the environment by default.

[malexan]

Also the function can in parallel save the table in rprtdata.