Minor release fixing some small issues.

This release also starts the transfer to models without strict inequalities. To test your code for this, use warning('on','YALMIP:strict'). If it complains, please update your model to prepare for future versions where strict inequalities no longer will be supported.

Overloaded the exponential integral.
Added the operator slog.
Fixed bug in overloaded log2.
Fixed bug in kkt causing an incorrect model when the inner problem problem had hidden equalities in the linear inequalities (YALMIP automatically extracts these in order to reduce the number of complicating complementarity constraints)
Fixed issue in dualize causing crash when having terms in models based on graph-based representations
Duals had wrong sign when Gurobi 5.0 was used.
Removed the demo directory. All demos were obsolete in terms of coding style, and new users are instead encouraged to learn from the Wiki.
Fixed issues related to solvers CBC, CLP, OOQP and BONMIN in OPTI Toolbox.