feat: slightly more expressive exception message

More datails in exception during header parsing.

arstomp/src/Helpers.cs

@@ -115,7 +115,7 @@ namespace ArStomp
 				var colon = line.IndexOf(":");
 				if (colon < 1) // must exist and cannot by first character in the line
 				{
-					throw new Exception("Cannot parse header");
+					throw new Exception($"Cannot parse header: colon not found. Cmd: {cmd}, line: `${line}`");
 				}
 				var key = line.Substring(0, colon);
 				var value = line.Substring(colon + 1);

arstomp/src/StompClient.cs

@@ -286,15 +286,8 @@ namespace ArStomp
 			var ct = Token.Token;
 			try
 			{
-				Frame fr = null;
-				try
-				{
-					fr = Helpers.GetFrame(msg.RawData, ct);
-				}
-				catch (Exception e)
-				{
-					throw e;
-				}
+				Frame fr = Helpers.GetFrame(msg.RawData, ct);
+
 				if (fr.Type == FrameType.Error) ExpectFrame(fr, FrameType.Message);
 				if (fr.Type == FrameType.Message)
 				{