(PUP-2950) Rubocop Style/Not automatic pass

This commit replaces `not` in favor of `!` where
can be done automatically (In places where the semantic meaning of the
expression does not change on replacing the `not` keyword with the operator `!`).

Since we are using `rubocop -a` to make the changes, we are assured of the
correctness of translation. These changes have also been individually verified.

This change is especially useful because after replacing such instances, the
AndOr cop can autocorrect even more instances of violations

This also enables the Style/Not cop
(PUP-2950) Rubocop Style/Not use consistant spacing

This commit ensures that no space is used between the application of
the operator `!` and its operand. That is, it replaces the instances of
`! mymethod` with `!mymethod`

It also enables the Style/SpaceAfterNot cop
(PUP-2950) Rubocop Style/AndOr automatic pass (2)

This commit replaces `and` and `or` keywords in favor of `&&` and `||` where it
can be done automatically (In places where the semantic meaning of the
expression does not change on replacing the `and` keyword with the operator `||`).

Since we are using `rubocop -a` to make the changes, we are assured of the
correctness of translation. These changes have also been individually verified.

This commit takes advantage of the previous changes replacing `not` keyword to
autocorrect even more instances of violations.