[ci skip] Add return values to examples
[ci skip] Consolidate docs for `first`

Add docs for `first` when provided a numerical argument. 

Since `first!` behaves exactly the same way but can raise an argument we can consolidate it in the `first` section.
[ci skip] Consolidate docs for `find_by`

Since `find_by!` behaves exactly the same way but can raise an argument we can consolidate it in the `find_by` section.
[ci skip] Consolidate docs for `take`

Add docs on what happens when a numerical argument is provided to take.

Since `take!` behaves exactly the same way but can raise an argument we can consolidate it in the `take` section.
[ci skip] Consolidate docs for `last`

Add docs on what happens when a numerical argument is provided to last.

Since `last!` behaves exactly the same way but can raise an argument we can consolidate it in the `last` section.
[ci skip] Consolidate docs for `find`

Put all options for overloading `find` in one section
[ci skip] Doc ability to chain in `find_each`

Also use appropriate mailer syntax in the `find_each` block.
[ci skip] Fix doc for except

The example showed is `except`, however the method "documented" is `unstop`. Fix to align the docs to the example.
[ci skip] remove invalid code from docs