Step-Importer: introduce new files.

code/Importer/StepFile/StepFileImporter.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <assimp/BaseImporter.h>
+
+namespace Assimp {
+namespace STEP {
+
+class StepFileImporter : public BaseImporter {
+public:
+    StepFileImporter();
+    ~StepFileImporter();
+    bool CanRead(const std::string& pFile, IOSystem* pIOHandler, bool checkSig) const override;
+    const aiImporterDesc* GetInfo() const override;
+
+protected:
+    void InternReadFile( const std::string& pFile, aiScene* pScene, IOSystem* pIOHandler ) override;
+
+private:
+};
+
+}
+}