Allow group on hatch.

[Baviaan]

Looks like I inadvertently closed #248 when I renamed my branch.

I suggested 1s leeway on the group command before throwing an invalid time error because a raid report does not store the given hatch time precisely:

# Program flow for !raid 5 here 18:00

stamp = await converter.convert(ctx, gym_split[-1]) # 18:00:00
dt = stamp - time.time()                            # 00:29:55 = 18:00:00 - 17:30:05
endtime = dt/60                                     # 00:29:55 /60
hatch = time.time() + 60*endtime                    # 18:00:00.1 = 17:30:05.1 + 00:29:55 * 60/60
                                                    # !group 18:00 throws an error

[Baviaan]

Changed the leeway to 1 min and allow 'hatch' as argument for a group time.

[Baviaan]

Changed it to get the current time once at the start of the function so there is no inconsistencies in what the 'current time' is between the five time() calls.

[Baviaan]

Updated to resolve the conflict with master that has been introduced the past year.