bug: Length time maxes out at 5:47:44 instead of showing real play time (24h)

[wizetek]

System Details
OS: Arch Linux
Arch: x64
Desktop Environment: Openbox X11
Version: 3.5.0
Installed by: pacman, compiled from git sources

Describe the bug
mp3 file that is 24h in play time shows in Cantata total time 5:47:44

To Reproduce
Steps to reproduce the behavior:

1. Add .mp3 file
2. Play
3. Examine the 'length' column/field

Expected behavior
Should show actual time 24:00:00

Screenshots
N/A

Additional context
N/A

[maxmitti]

The issue is that Cantata stores the play time in seconds in an unsigned 16 bit integer.
The time doesn’t actually max out at 5 hours plus something, but this is what 24 hours in seconds truncated to 16 bit equals.
The maximum should be 18:12:15.

@nullobsi, should we simply change Song::time to quint32 and update relevant references?