dataframe_from_rpt fails if more than one element is provided in the section

[kristianfoerster]

Starting with version 0.4.0 dataframe_from_rpt only works properly if only one element exists in the corresponding section. If there are more than one element (e.g., subcatchments), the returned pd.DataFrame object is invalid, since it includes the results of all elements as well as the string comments between the time series. I was wondering if it's worth to add the element_id argument to the function call (as it was available in swmmio-0.3.x. Thank you!

[aerispaha]

Thanks for catching this @kristianfoerster! I think I have a fix to restore this feature in the dev branch here