Feature/remove double negation from ast

[hardbyte]

Removes the DoubleMinus and DoubleNot from the AST.

Also after noting in the spec:

We only support positive, decimal integer literals; negative integers are produced by the unary negation operator.

I removed the -? before the integer and unsigned integer parsing.

One case is no longer handled correctly by the LARLPOP parser !!member. I've changed the test for now to !(!... hoping you know how to handle this properly?

[clarkmcc]

Closing since this would cause a behavior regression in its current state. Can reopen in the future if needed