faster addRow operation for LP

[Tapolcai János]

A new function is requested in lp_base.h:

virtual int _addRow(ConstRowIterator?, ConstRowIterator?, Value, Value) =0;

int this cae the following two function can be replaced in lp_base.h 1.

Row addRow(Value l,const Expr &e, Value u) {

Row r=addRow(); row(r,l,e,u); return r;

}

by

Row addRow(Value l,const Expr &e, Value u) {

Row r;

e.simplify(); r.id = _addRow(ConstRowIterator?(e.begin(), *this),

ConstRowIterator?(e.end(), *this),l-e.constComp(),u-e.constComp() );

return r;

}

2.

Row addRow(const Constr &c) {

Row r=addRow(); row(r,c); return r;

}

by

Row addRow(const Constr &c) {

Row r=addRow(c.lowerBounded()?c.lowerBound():-INF,

c.expr(), c.upperBounded()?c.upperBound():INF);

return r;

}

For each solver a new int _addRow(ConstRowIterator?, ConstRowIterator?, Value, Value) function must be implemented (see also the attached files).