Remove Guzzle library

[trandangtri]

Close #34

[mvar]

@trandangtri you cannot call real 3rd party service in your tests. You should mock it somehow.

[saimaz]

@trandangtri the issue is about to make it OPTIONAL not to REMOVE.

[saimaz]

Guzzle has a http mock. You can use it to simulate actual request to openexchange service by pretending that it works.

[trandangtri]

The OpenExchangeDriver just calls a normal json request to a 3rd party service, I dont think we need to use Guzzle. That's why I do suggest replace it by a curl request.

[saimaz]

Disagree. Guzzle is perfect object oriented HTTP client, which is has tests, is testable and well maintained. OpenExchange rate is one of many 3rd party providers for currency. Normally when somebody will use this bundle they will need a HTTP connection anyway. So to give an advice for user to install Guzzle is nice to have IMO.

[saimaz]

The only way to test a native curl function would be to use aspect oriented mocking library which would be hardcore style 😄

[murnieza]

Another advantage of using Guzzle is easily controllable logging.

I also think that it should not be replaced with plain curl.

[trandangtri]

I misunderstood this issue. I think I should close this and will back with a new PR