Revert "Merge branch 'hotfix/exclude-timeofday'"

This reverts commit adb3de0934f3209738353a034bb672b0e0b77e08, reversing
changes made to cb5173ffcb9296717798081d7789647563fd9064.
Revert "Merge branch 'hotfix/exclude-timeofday'"

This reverts commit 3150202269da7a0b02d0191cf6143980d8b2071b, reversing
changes made to cb5173ffcb9296717798081d7789647563fd9064.
Added a note to timeofday chart.
Merge branch 'hotfix/timeofday-comment'
Display the average number of instances per device.
Merge branch 'feature/activities-per-device'
Show the number of devices in statistics from database.
Display the average number of instances per device.
Merge branch 'feature/activities-per-device'
Merge branch 'feature/show-db-stats'

Conflicts:
	lib/activity_avg_count.js