31 import data frame

changed previous importData to importDataByFile.
made a new importData function, it takes a dataframe, makes a temporary .txt file out of it and then makes a .pgex.

a datasource can be said, if not, the datasource is guessed by the program. If there are more than one datasources possible it returns the possibilities.

source can also be set manually with a parameter, for this parameter both a full name and a system code can be used