errorlib: fix time-constrained emergency test case

• In test_get_emergency_recipients(), when ran test case at certain hours and minute it failed. Var hour is calculated with "mod 24" (hour must be in (0..23) and var minute with "mod 60" (minute must be in 0..59). (closes #421)

• Recalculated var hour and var earlier in constraint_near_miss when var minute changes and it means changing hour.