Limit number of treatments imported from NovoPens

[m-hoerz]

After recently trying out the pen feature with my NovoPen 6 I noticed one gets into rather much fuss if one doesn't use the pen from the very beginning. In my case a had 100s of duplicate entries I had to remove by tapping undo for minutes.

Thus I would suggest either a duplicate detection by checking if a treatment with the same dose already exists within a certain time window (3 minutes?) or a rather simple approach: just define a certain date/time before which treatments never should get imported.