Silverstripe 5 compatibility

[baukezwaan]

First try to make it compatible with ss5.
Let me know if you rather like to have it on seperate ss5-branch and only ss5 requirements.

[bummzack]

Thanks for this! Have you tested this with SS5 already? If it's just updated composer requirements, this could just go into the current main branch

[baukezwaan]

Yep, works fine on a SS5 installation, I'm using in the wild today 🚀

[bummzack]

Thanks, much appreciated!