Add Lua bindings to SetDensityIndependentPixelRatio/GetDensityIndependentPixelRatio (as an attribute)

[shubin]

Add dp_ratio attribute to the Lua binding of Rml::Context providing access to its SetDensityIndependentPixelRatio and GetDensityIndependentPixelRatio methods

[mikke89]

Thanks for another Lua improvement!

This looks good to me, but is marked as a draft still, are you happy with how it looks?

The commit history is a bit messy, but I'll just squash it and then it's all good. In the future, it might be easier to create separate feature branches intended for pull requests.

[shubin]

Yeah, I've been worrying about the messy commit history as well.

The code itself is very simple. I'm not 100% sure about the naming - I've decided to name the property as "dp_ratio" and I thought that you might want to name it differently.

Thank you for your hint, will use feature branches for the future pull requests!

[mikke89]

Yeah, I'm happy with dp_ratio as a property as long as it's documented, I think that makes the most sense.

Thanks a lot for the PR!

[shubin]

I'm glad that my contribution is helpful!
I will make a pull request to the documentation a bit later.