Make proxies optional

[vieiralucas]

Hello, this is my proposal for solving #766

First of all, thank you @meeber for describing what, where and how to do this.
All I had to do was add the code. You are awesome.

Please let me know if I'm missing something here.

Thank you all ❤️

[lucasfcosta]

Nitpicky Warning: The word define here should be written as defines, shouldn't it?
(Please correct me if I'm wrong, I'm not a native speaker)

[meeber]

Agreed on "defines" over "define".

Also maybe be a bit more explicit on the purpose of this feature. For example adding onto the end:

"...non-existent property is read, which protects users from typos when using property-based assertions."

[vieiralucas]

Agreed with both you guys. I will add the suggestions.
Thanks

[lucasfcosta]

BTW I forgot to thank you for this awesome PR.
Since we get to talk to each other almost everyday on college I forgot that.
Just left some minor notes about grammar and another thought I had about test's coverage.

[meeber]

@vieiralucas Awesome work sir. Thanks for doing this :D

It looks like you already fixed one of the two line comments I made while reviewing. Once the other is resolved I think this is set to merge.

Btw, how does one go about joining the Lucas Syndicate? Is being named Lucas a hard requirement?

[meeber]

LGTM :D

[vieiralucas]

@meeber Thank you, and all the maintainers of chai for making this project such a friendly place to new contributors.

I believe that being named Lucas would be a requirement for joining our Syndicate, but maybe we can add an exception for you.

[meeber]

I just had another thought on this: We should mention that this feature is automatically disabled regardless of this config value in environments that don't support proxies.

[vieiralucas]

Agreed, should I put this before the example or after?

  /**
   * ### config.useProxy
   *
   * User configurable property, defines if chai will use a Proxy to throw
   * an error when a non-existent property is read, which protects users
   * from typos when using property-based assertions.
   * This feature is automatically disabled regardless of this config value
   * in environments that don`t support proxies.
   *
   * Set it to false if you want to disable this feature.
   *
   *     chai.config.useProxy = false;  // disable use of Proxy
   *
   * @param {Boolean}
   * @api public
   */

vs

  /**
   * ### config.useProxy
   *
   * User configurable property, defines if chai will use a Proxy to throw
   * an error when a non-existent property is read, which protects users
   * from typos when using property-based assertions.
   *
   * Set it to false if you want to disable this feature.
   *
   *     chai.config.useProxy = false;  // disable use of Proxy
   *
   * This feature is automatically disabled regardless of this config value
   * in environments that don`t support proxies.
   *
   * @param {Boolean}
   * @api public
   */

[meeber]

I like the second

[vieiralucas]

Done

[meeber]

LGTM

[lucasfcosta]

LGTM too.