Rework on combining multiple strategies.

[jbdelmundo]

Description: The combination could be as

1. Diversified Strategy: works for diversifying strategies
2. Combine signals under 1 strategy

Detailed example: Assume that different signals for Strategy 1 and Strategy 2 occurs on the following timestamps

Timestamp	Strategy 1	Strategy 2	Diversified Strategy	Combined signal OR	Combined signal AND
1	BUY		BUY1	BUY
2
3		BUY	BUY2
4	SELL		SELL1	SELL
5		SELL	SELL2
6	BUY	BUY	BUY 1&2	BUY	BUY
7
8	SELL	SELL	SELL 1&2	SELL	SELL
9

For Diversified Strategy:

• It works as if the two strategies are implemented at the same time.
• Note that it allows consecutive Buy Signals at timestamp 1 and 3 (from Strat 1 and Strat 2 respectively)
• It might require additional parameter such as position_size to allow consecutive buy signals and sell signals
• This assumes that there are 2 different strategies that triggers the 2 trades

For Combined Signal OR

• The buy or sell signal is generated if ANY of the signals of the strategies are sent
• Unlike the Diversified Strategy it would not allow consecutive buy and sell signals

For Combined Signal AND

• The buy or sell signal is generated if ALL of the signals of the strategies are sent