Couenne Stable Release 0.4 Announced

This is to announce the 0.4 stable version of Couenne. There are a number
of additions and improvements, including:

1) a Feasibility Pump heuristic for non-convex MINLP, developed with Timo
Berthold at the ZIB institute.

2) Orbital Branching for MINLP, developed with Jim Ostrowski and Leo
Liberti.

3) Fixed Point Bound tightening, a bound reduction procedure developed
with Sonia Cafieri, Jon Lee, and Leo Liberti.

4) "semi-auxiliaries", i.e., auxiliary variables defined as y >= f(x) or y
<= f(x) instead of just y = f(x). The purpose is to save on the number of
auxiliaries generated and hence on the size of the LP relaxation.

5) "Two-Implied bound tightening", a new bound reduction procedure
described in http://www.optimization-online.org/DB_FILE/2011/02/2931.pdf

6) various bug fixes.

Release 0.4.0 is a snapshot of the new stable version. The new features
will soon be documented in Couenne's user manual, available at
http://www.coin-or.org/Couenne/couenne-user-manual.pdf