Implement POST and DELETE end-points.

Hello,
it would be very useful if you can modify the http.Client inside the Client struct.
For example for replacing http.Client.Transport to get your own response caching or rate limiting. Or changing timeouts.
I did not submit a PR because there are multiple ways to do it (exporting Client.http, adding a parameter to Init(), adding a new method(s) to Client...). But the change should be trivial.

Thank you.

Get rid of the magic numbers.

https://github.com/cyruzin/golang-tmdb/blob/master/helpers.go

Sometimes the TMDb API adds new features and I don't know because I don't check the documentation often.

I would like to request adding support for TMDB API access token in the golang-tmdb library. Currently, the library only supports API key authentication.

https://developers.themoviedb.org/4/getting-started/authorization

Is your feature request related to a problem? Please describe.
Not a problem.

Describe the solution you'd like
Implement a image/video helper that returns the complete url.

Describe alternatives you've considered
None.

Additional context
None.

when GetMovieChanges or append_to_resonse used with changes as one of value the changes struct after marshal always has same weird string

On left I'm printing value before marshal and it's fine but after marshal result is weird string doesn't matter what movie I fetch

Different movie same string after marshal

Is your feature request related to a problem? Please describe.
I think that some variables names aren't good.

Describe the solution you'd like
Rename them. One letter is hard to reason about. Improve the code in general.

Describe alternatives you've considered
None for this issue.

Additional context
None.

Currently, only get method is working well.

It need to be easy to maintain. Just a few tweaks.

Is your feature request related to a problem? Please describe.
It's not a problem. Implement http request with context.

Describe the solution you'd like
Requests with context without any breaking changes.

Describe alternatives you've considered
None, the standard lib is enough.

Additional context
https://golang.org/pkg/net/http/#NewRequestWithContext

Refactor comments, some structs names and break big functions into multiple lines.

In options map with key append_to_response = "provider" doesn't work

Hey @cyruzin,
I am having problems getting the ConfigurationCountries by calling GetConfigurationCountries. It seems like the return type is *ConfigurationCountries which is a pointer to a []struct.
How can I iterate over that struct and extract the fields(Iso3166_1 and EnglishName)? It is also likely that this is obvious and I am just a bit dumb right know 😅

Would be great if you can give me an example.
Thanks
Tim 😊

Nice feature.

Is your feature request related to a problem? Please describe.
It's not a problem, it is just for checking how the lib is performing.

Describe the solution you'd like
Check the metrics and improve the speed.

Describe alternatives you've considered
Use jsoniter lib to encode/decode faster. Avoid allocations.

Additional context
https://github.com/json-iterator/go

Is your feature request related to a problem? Please describe.
Most (all?) results structure are embedded and not exportable, which made impossible to merge all results from many pages to one list

Describe the solution you'd like
Export 'results' structure

Describe alternatives you've considered
I've to create a list from the parent structure and do a double 'for' to iterate over all results

Additional context
For example

Is your feature request related to a problem? Please describe.
other packages using the client cannot write a unit test because the baseURL variable cannot be modified and can only access the real tmdb address.

Describe the solution you'd like
add a method to modify baseURL

Describe alternatives you've considered

Additional context

Describe the bug
JSON Metadata for Iso3166_1 is json:"iso_31661_1" right now, it should be json:"iso_3166_1" instead as documented here: https://developers.themoviedb.org/3/movies/get-movie-details

To Reproduce
Call GetMovieDetails for any movie and checkout MovieDetails.ProductionCountries[0].Iso3166_1