Fix Matlab static interface generation

Matlab static generation was not generated as stated in #1777
This patch would not be possible without the help of @yage99 !

CMakeLists.txt

@@ -191,7 +191,7 @@ ENDIF()
 
 # this has been only fixed in swig 2.0.12 or later.
 IF (NOT ((CYGWIN AND ENABLE_TESTING) OR (DARWIN AND COMPILE_MODULAR_INTERFACE
-	AND SWIG_VERSION VERSION_LESS "2.0.12")))
+	AND SWIG_VERSION VERSION_LESS "2.0.12") OR MatlabStatic))
 	INCLUDE(CheckCXX11Features)
 
 	IF(_HAS_CXX11_FLAG)
@@ -950,7 +950,7 @@ ENDIF()
 IF (MatlabStatic)
 	FIND_PACKAGE(Matlab REQUIRED)
 	IF(MATLAB_FOUND)
-		IF(EXISTS ${CMAKE_SOURCE_DIR}/src/interfaces/matlab_modular)
+		IF(EXISTS ${CMAKE_SOURCE_DIR}/src/interfaces/matlab_static)
 			add_subdirectory(${CMAKE_SOURCE_DIR}/src/interfaces/matlab_static)
 		ENDIF()
 	ELSE()

src/interfaces/matlab_static/CMakeLists.txt

@@ -1,4 +1,5 @@
-include_directories(${MATLAB_INCLUDE_DIR})
-
-add_library(matlab_static SHARED MatlabInterface.cpp)
-target_link_libraries(matlab_static shogun ${MATLAB_LIBRARIES})
+ADD_CUSTOM_TARGET(matlab_static ALL
+	COMMAND "${MATLAB_ROOT}/bin/mex" -o sg -I${CMAKE_SOURCE_DIR}/src ${CMAKE_CURRENT_SOURCE_DIR}/MatlabInterface.cpp $<TARGET_SONAME_FILE:shogun>
+	DEPENDS shogun
+	WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+	COMMENT "Compiling MATLAB static interface")