Port to PHP 8

[duboism]

This PR ports the code to PHP 8 (including PHP 8.4).

For now we use the master branch of Image_Color from https://github.com/duboism/Image_Canvas/ because we need a version that runs on PHP 8. This has to be changed before merging. This was changed in 3b4d483.

What was changed

• correct constructor
• several functions have been declared static
• correct a call to implode

[Neustradamus]

@duboism: "Image_Colorfrom" bad text ^^

It must be:

• https://github.com/pear/Image_Color

Hope that @ashnazg will add "Issues" section in specified repos...

[duboism]

@duboism: "Image_Colorfrom" bad text ^^

It must be:

* https://github.com/pear/Image_Color

Good catch. Corrected.

[ashnazg]

@duboism , looks good to me... go ahead and undo the master/repo addition in composer.json, and I'll get it merged after.

[duboism]

@ashnazg, thanks for your time. The problem is that the latest tag on pear/image_color (1.0.6) is not compatible with PHP 8.

I have described this on PEAR ML in the (long) thread titled "Port Image_Color and Image_Canvas to PHP8": after the latest PRs, Image_Color works on PHP 8 so one just need to create a new tag and publish it on packagist and then I can finish this PR. Could you do that ?

[ashnazg]

@duboism , I've generated new release Image-Color-1.0.7, so you can now do your update here.

[duboism]

@ashnazg, I did it (see 3b4d483). I will edit the description and remove the draft status.

[duboism]

OK, I think everything is ready to merge now.

[ashnazg]

Included in v0.5.0 release.

[Neustradamus]

Thanks to @duboism for this PR and @ashnazg for merging and the new release build!

[duboism]

Thanks @ashnazg for merging this and for the tag.