README.md - Wrong object syntax

[guerreiropedr0]

In the README.md file, there are some inconsistencies resolving object syntax.

Example:
brushArc({ fillStyle = 'black', size = 10 })

It should be:
brushArc({ fillStyle: 'black', size: 10 })

[sasza2]

the whole idea behind = was to show default values of these functions. let me think about your changes:D hmm, maybe I would just add typings to be more clear. anyway, thanks for PR!

[guerreiropedr0]

Oh, that makes sense! It isn't very clear though, at least in my opinion. Anyways, it is a nice project so thank you. Happy coding 😄