Throw exception for type mismatch in StreamingAlgorithmWrapper

Throw a more informative exception on type mismatch in
StreamingAlgorithmWrapper. When the declared type for streaming mode
cannot be matched to the types in standard mode implementation, an
exception will occur (for example, #674). Improve its message text.

src/essentia/streaming/streamingalgorithmwrapper.cpp

@@ -107,21 +107,40 @@ void StreamingAlgorithmWrapper::declareOutput(SourceBase& source, NumeralType ty
 
 
 void StreamingAlgorithmWrapper::synchronizeInput(const std::string& name) {
-  if (_inputType[name] == TOKEN) {
-    _algorithm->input(name).setSinkFirstToken(*_inputs[name]);
+  try {
+    if (_inputType[name] == TOKEN) {
+      _algorithm->input(name).setSinkFirstToken(*_inputs[name]);
+    }
+    else if (_inputType[name] == STREAM) {
+      _algorithm->input(name).setSinkTokens(*_inputs[name]);
+    }
   }
-  else if (_inputType[name] == STREAM) {
-    _algorithm->input(name).setSinkTokens(*_inputs[name]);
+  catch(EssentiaException& e) {
+    std::ostringstream msg;
+    msg << "While wrapping '" << _algorithm->input(name).name()
+        << "' input in the streaming algorithm wrapper for " 
+        << _algorithm->name() << ":\n" << e.what();
+    throw EssentiaException(msg);
   }
 }
 
 
 void StreamingAlgorithmWrapper::synchronizeOutput(const std::string& name) {
-  if (_outputType[name] == TOKEN) {
-    _algorithm->output(name).setSourceFirstToken(*_outputs[name]);
+  try {
+    if (_outputType[name] == TOKEN) {
+      _algorithm->output(name).setSourceFirstToken(*_outputs[name]);
+    }
+    else if (_outputType[name] == STREAM) {
+      _algorithm->output(name).setSourceTokens(*_outputs[name]);
+    }
   }
-  else if (_outputType[name] == STREAM) {
-    _algorithm->output(name).setSourceTokens(*_outputs[name]);
+  catch(EssentiaException& e) {
+    std::ostringstream msg;
+    msg << "While wrapping '" << _algorithm->output(name).name()
+        << "' output in the streaming algorithm wrapper for " 
+        << _algorithm->name() << ":\n" << e.what();
+    throw EssentiaException(msg);
+    throw EssentiaException(msg);
   }
 }