ControlExpression: fix cloning of expressions and implement SE algorithm
ControlExpression: fix cloning of expressions and implement SE algorithm

implement basic state elimination algorithm in ControlExpression class

Signed-off-by: Marek Chalupa <a05df156a69ad59faa9af9b666ef78009594c145@gmail.com>

mchalupa/dg,mchalupa/dg,mchalupa/dg,mchalupa/dg