Support additional strategies about avarice HOT 2 CLOSED

Good documentation in a "Configuring" section is going to be key for this to succeed, but here's how it's looking so far:

• Support for Volatility indicators are only functional when combined with at least one non-volatility indicator.
• You can make combined (requiring all signals to align) and independent indicators co-exist in TradeIndicators. For instance, if you wanted to trade MACD only when BollBandwidth is above the set threshold yet also have FullStochRSID trade independently, you would set: TradeIndicators = [['MACD', 'BollBandwidth'], 'FullStochRSID']
• Each indicator class in genconfig has a Trader nested class with TradeVolume, SingleTrade, TradePersist, and TradeDelay. These additional options are only used if that indicator is an independent indicator (not combined with another indicator). For combined indicators, these options are used from genconfig Trader.
• If a custom strategy is written in strategies.py, it may be set in AdvancedStrategy instead of "default"

This maintains all current functionality since the currently functional configurations may still be used in genconfig without any changes. However it also adds much more advanced functionality.

from avarice.

The first part of this rewrite was just pushed to the strat-rewrite branch here

from avarice.