Minor debug message fixes.

dyaml/node.d

@@ -973,7 +973,7 @@ struct Node
         int opApply(T)(int delegate(ref T) dg) @trusted
         {
             enforce(isSequence, 
-                    new Error("Trying to sequence-foreach over a " ~ nodeTypeString ~ "node",
+                    new Error("Trying to sequence-foreach over a " ~ nodeTypeString ~ " node",
                               startMark_));
 
             int result = 0;

dyaml/parser.d

@@ -517,7 +517,7 @@ final class Parser
 
             immutable token = scanner_.peekToken();
             throw new Error("While parsing a " ~ (block ? "block" : "flow") ~ " node", 
-                            startMark, "expected the node content, but found: " 
+                            startMark, "expected node content, but found: " 
                             ~ token.idString, token.startMark);
         }