Incorrect type declarations for clear() and createFramebuffer()

[christopherball]

Tested on v1.7.4

Error 1:

The p5.js implementation shows that these are optional parameters and don't need to be passed in as they default to a value of 0, so the only way around is to add // @ts-ignore statements to bypass (or unnecessarily spell out every parameter).

Error 2:

The p5.js implementation shows that this method returns an actual p5.Framebuffer (not void), so the only way around is to add // @ts-ignore statements to bypass.

[christopherball]

Thanks @asukaminato0721