Java API: renamed assert_(...) to add(...)

.NET API: added alias Add(...) for Assert(...)

Signed-off-by: Christoph M. Wintersteiger <cwinter@microsoft.com>

src/api/dotnet/Solver.cs

@@ -117,6 +117,14 @@ namespace Microsoft.Z3
             }
         }
 
+        /// <summary>
+        /// Alias for Assert.
+        /// </summary>        
+        public void Add(params BoolExpr[] constraints)
+        {
+            Assert(constraints);
+        }
+
         /// <summary>
         /// Assert multiple constraints into the solver, and track them (in the unsat) core 
         /// using the Boolean constants in ps.