Fix Instance Variable Assumption false positive

[JuanVqz]

Can you please have a look?

I hope this fixes #1492

What this basically does is look up through all the initializers if it matches the ivasgn to consider it instance variable assumption.

[troessner]

Hey @JuanVqz ,

that does look nice! @mvz any comments?

[JuanVqz]

@troessner and @mvz thank you for having a look, I rebased it :+1:

[mvz]

Thanks @JuanVqz!