StopTrail is based on the candle high, not close

[nuno84]

Hi,
I would like to propose the following change.
By doing some developing, I noticed that the trail stop was based on the candle Close, but I think it is incorrect and should be done on the candle high:
I did a trailing stop of 5%

Before it was 99.9 - 5% = 94.905:

After it is 102.23 - 5% = 97.11 as we can see in the sell:

Tks

[smalinin]

Simply change to on High is not a good idea:

1. it work properly only for Buy, not for Sell orders
2. BackBroker is just a simulation, if you use High price, we must to add some slip value, because High price could be with Volume==1(for example), when you have order size=500. So Close give more adequate/real results.

Therefore it could be added, but it must be configurable, with default on Close and more properly work for both Buy/Sell orders.
I will look it later.