Fix 8.3. Tesselation

- CMake: Handle *.tcs and *.tes shader files
- avoid directory name “resources”, since it triggers weird behaviour of glfwInit() on mac os (see remarks at https://www.glfw.org/docs/3.3/group__init.html#ga317aac130a235ab08c6db0834907d85e)
- shader loader: print exception messages

includes/learnopengl/shader_t.h

@@ -76,7 +76,8 @@ public:
         }
         catch (std::ifstream::failure& e)
         {
-            std::cout << "ERROR::SHADER::FILE_NOT_SUCCESSFULLY_READ" << std::endl;
+            std::cout << "ERROR::SHADER::FILE_NOT_SUCCESSFULLY_READ: " 
+                << e.what() << std::endl;
         }
         const char* vShaderCode = vertexCode.c_str();
         const char * fShaderCode = fragmentCode.c_str();
@@ -232,4 +233,4 @@ private:
         }
     }
 };
-#endif
+#endif