handle commas in pandda_inspect_events.csv comments

[elmjag]

The pandda inspect CSV file allows to specify comments for each event via 'Comment' column.

However, the FragMAXapp does not parse the 'Comment' cells properly if the comment contains commas.
The comment get's truncated at first comma in the FragMAX UI.

Here is an example file:
pandda_inspect_events.csv

Fix parsing of pandda_inspect_events.csv file to handle this correctly. We should probably switch to use pandas.read_csv(), instead of our home-grown CSV parser.