register kernel as CKernel* to make put work in cpp

examples/meta/src/meta_api/kwargs.sg

@@ -26,10 +26,23 @@
 # KernelMachine svm2 = kernel_machine("LibSVM", kernel=kernel("GaussianKernel"))
 
 
-
 # Real example
 # ------------
 
+RealMatrix matrix(1,2)
+matrix[0,0] = 0.0
+matrix[0,1] = 0.1
+
+RealFeatures features()
+features.put("feature_matrix", matrix)
+
+RealVector vector(2)
+vector[0] = 0.0
+vector[1] = 0.1
+
+RegressionLabels labels()
+labels.put("labels", vector)
+
 Kernel k = kernel("GaussianKernel", log_width=2.0)
 KernelMachine svm = kernel_machine("LibSVM", C1=1.1, kernel=k)
 

src/shogun/base/SGObject.h

@@ -364,24 +364,13 @@ class CSGObject
 		}
 	}
 
-#ifndef SWIG
-	template <typename T, std::enable_if_t<std::is_convertible<T, CSGObject*>::value>* = nullptr>
-	[[deprecated ("SGObject parameters should be registered as a base class.")]]
-	void put(const std::string& name, const T value)
-	{
-		CSGObject* v = value;
-		Tag<CSGObject*> tag(name);
-		put(tag, v);
-	}
-#endif
-
 	/** Setter for a class parameter, identified by a name.
 	 * Throws an exception if the class does not have such a parameter.
 	 *
 	 * @param name name of the parameter
 	 * @param value value of the parameter along with type information
 	 */
-	template<typename T, typename U = typename std::enable_if_t<!std::is_convertible<T, CSGObject*>::value>>
+	template <typename T, typename U = void>
 	void put(const std::string& name, const T value) throw(ShogunException)
 	{
 		Tag<T> tag(name);

src/shogun/machine/KernelMachine.cpp

@@ -634,7 +634,11 @@ void CKernelMachine::init()
 	use_linadd=true;
 	use_bias=true;
 
-	SG_ADD((CSGObject**) &kernel, "kernel", "", MS_AVAILABLE);
+	//	SG_ADD((CSGObject**) &kernel, "kernel", "", MS_AVAILABLE);
+	m_parameters->add((CSGObject**)&kernel, "kernel", "");
+	watch_param(
+	    "kernel", &kernel,
+	    AnyParameterProperties("", MS_NOT_AVAILABLE, GRADIENT_NOT_AVAILABLE));
 	SG_ADD((CSGObject**) &m_custom_kernel, "custom_kernel", "Custom kernel for"
 			" data lock", MS_NOT_AVAILABLE);
 	SG_ADD((CSGObject**) &m_kernel_backup, "kernel_backup",