Actually this function is useless and potentially dangerous, internally, a shallow copy of data was done. Same could be accomplished accesing image.data directly.

To unify with DrawText*() equivalent functions

Now it's blazing fast. It modifies image.data directly.

Previous version could take up to 3-4 seconds to draw a line... now it takes some nanoseconds...

* Update ImageDraw*() functions to match arguments of Draw*()

Updated draw functions:
ImageDrawPixel()
ImageDrawPixelV()
ImageDrawCircle()
ImageDrawCircleV()
ImageDrawLine()
ImageDrawLineV()
ImageDrawRectangle()
ImageDrawRectangleV()
ImageDrawRectangleRec()

* [nodepadpp] Update Notepad++ ImageDraw defintions

This updates the Notepad++ definitions with the updated ImageDraw methods.

* [examples] Add ImageDraw calls to textures_image_drawing

* Update ImageDraw*() methods

Added draw functions:
ImageClearBackground()
ImageDrawPixel()
ImageDrawLineEx()
ImageDrawCircle()

NOTE: Two libraries still use custom allocators: glfw and stb_vorbis

NOTE: This functionality has an important issue, line space is fixed to 1.5 font.baseSize pixels, depending on the font and how it has been generated that spacing could be too wide or too narrow...

Use new file I/O ABI

Using new file I/O ABI

Using new file I/O ABI

Just for clarification, no plans to remove libc dependency, just did some code analysis to see how much raylib depend on stardard C library. My conclusions:

 - stdlib.h: primary dependency is for malloc() and free()
 - stdio.h: primary dependency is for FILE access, maybe it could go through a custom ABI?
 - string.h: just around 8 functions required
 - math.h: just around 8 functions required
 - others: 1-2 functions required for some other headers

Added SUPPORT_TRACELOG_DEBUG config

* explained a bit more the core_window_letterbox example

* fixed a few 'ups' moments that could lead to mild head pain and time loss

When adding alpha mask to GRAYSCALE image, if using ImageFormat(), it could change pixel values, now we avoid that, mask is just added as an extra channel

Still looking for a better way to integrate it into raylib API, maybe add a LoadImageAnim()?

Fix build failure introduced in 2a913b6587