fixes KBH import hop times

[prash3r]

fixes #100

my test recipe looks like this:

and the relevant part of the resulting sqlite table looks like this:

If you look at the column Vorderwuerze you see that there are different Values possible then 0 or 1. From my testing and understanding it should work like this:

1. Vorderwürze=pre_boil=1
2. Kochbeginn=boil_start=2
3. Kochen=boiling=3
4. Kochende=boiling_finish=4
5. Ausschlag=Wirlpool=5

Since the time value is still provided i hope i can just differentiate between Vorderwürze=1 and all others <> 1 to create the intended result.

With my test recipe it seems to work out great:

EDIT:
I tested the negative hop timer value for Whirlpool additions and the notification is of course missing. Alle the other notifications came as expected so i guess this still fixes the issue at hand.

[avollkopf]

Currently, activity is only on my branch. I will change it there in the development branch, but will disable the '5' for now as negative times are not supported.