Calendar view groups logs by exercise

[rolandgeider]

The (day) calendar view groups the logs by exercise. While this is most of the time correct, this is simply wrong when doing supersets, at it then appears that all weights were logged for one exercise, then for another. This will also become more relevant when issue #64 is implemented. Eg:

Ex. A 10 reps, 10 kg.
Ex. B 7  reps,  5 kg.
Ex. A 10 reps, 11 kg.
Ex. B 7  reps,  5 kg.
Ex. B 8  reps,  5 kg.

results in

Ex A: 10 reps, 10 kg., 10 reps, 11 kg.
Ex B: 7  reps, 5  kg., 7  reps, 5  kg., 8 reps, 5 kg.

The day view should present a list of logs. Bonus points if they are grouped by exercise only if they really were logged together. There is a cache for the logs, it will probably has to be changed in some way for this.