default function performs no operation (NoOp), returns orderqty
osNoOp(timestamp, orderqty, portfolio, symbol, ruletype, ...)
timestamp coercible to POSIXct that will be the time the order will be inserted on
numeric quantity of the desired order, modified by osFUN
text name of the portfolio to place orders in
identifier of the instrument to place orders for. The name of any associated price objects (xts prices, usually OHLC) should match these
one of "risk","order","rebalance","exit","enter", see add.rule
any other passthru parameters
if orderqty 'all', will only work on an exit rule type, otherwize orderqty is zero.