GL/GLFW Example Displays GLAD Version "0.1"
The GL/GLFW example located at `example/c/gl_glfw.c` (shown below) loads GL with `glfwGetProcAddress`:
```c
int version = gladLoadGL(glfwGetProcAddress);
```

However, when loading with GLFW (and glad2) for OpenGL 4.6, `gladLoadGL(GLADloadfunc)` returns `1`. Thus, when retrieving the major and minor versions of OpenGL, `"0.1"` is generated.

I'm not sure if this is intentional, because I would expect this to return either the current GLAD version or the current GL version, however only `1` is ever returned from `gladLoadGL`.

I don't think this issue is cause for any immediately obvious problems with the loader, but I worry about portability in the future. Is this the incorrect way to retrieve the OpenGL version loaded by glad? If so, what should be done instead?

Thank you for reading.

Contents of `example/c/gl_glfw.c`

```c
#include <glad/gl.h>
// GLFW (include after glad)
#include <GLFW/glfw3.h>

#include <stdlib.h>
#include <stdio.h>


const GLuint WIDTH = 800, HEIGHT = 600;

void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode) {
    if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
        glfwSetWindowShouldClose(window, GL_TRUE);
}

int main(void) {
    glfwInit();

    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 6);
    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);

    GLFWwindow* window = glfwCreateWindow(WIDTH, HEIGHT, "[glad] GL with GLFW", NULL, NULL);
    glfwMakeContextCurrent(window);

    glfwSetKeyCallback(window, key_callback);

    int version = gladLoadGL(glfwGetProcAddress);
    printf("GL %d.%d\n", GLAD_VERSION_MAJOR(version), GLAD_VERSION_MINOR(version)); // <-- prints "GL 0.1"

    while (!glfwWindowShouldClose(window)) {
        glfwPollEvents();

        glClearColor(0.7f, 0.9f, 0.1f, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT);

        glfwSwapBuffers(window);
    }

    glfwTerminate();

    return 0;
}
```