Handle expected boolean values for waiter error matcher

[jterapin]

All services currently define waiter error acceptors that have expected string values that represent an AWS Error code like below:

{
  "expected":"ResourceNotFoundFault",
  "matcher":"error",
  "state":"success"
}

A waiter with this acceptor will continue to wait until an error the the code ResourceNotFoundFault is received or the max amount of attempts is reached.

However, it's possible for service teams to define a waiter error acceptor like below which has an expected boolean (true or false) value. The expected behavior is defined below:

true - Match an error code with any value.
false - Match if no errors were encountered

Example:

{
  "matcher" : "error",
  "expected" : false,
  "state" : "success"
}

A waiter with this acceptor will continue to wait until a response with no error is received or the max amount of attempts is reached.

This PR adds the ability for waiters to handle the acceptors described above.

---

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Thank you for your contribution!

[jterapin]

I plan do some rubocop adjustments once the PR has been approved. Keeping as it is to help out with readability.

[jterapin]

Moving to Draft mode since I need to do some audits and add/update existing waiter specs

[jterapin]

Self-reminder: Revert 1a61acd after approvals

[alextwoods]

Nice - great additional tests.