Support multipart requests

[mukel]

Very slick library, but can't send multipart requests out-of-the-box. Other libraries I've tried do support it but have other caveats:

• RosHttp but not as nice as this one (and a bit buggy).
• sttp but doesn't support Node.js ATM.

[pepegar]

Hey @mukel ! Yeah, multipart is something we definitely want to introduce. I think the idea would be to create a new MultipartEntity, and map it to the underlying implementations.

[pepegar]

CC/ @antonkulaga

[pepegar]

Working on it now

[antonkulaga]

@pepegar any updates?

[pepegar]

Hi @antonkulaga. I haven't had much time lately to invest in Hammock. I'll try to update it here when feature gets to a reviewable state.

[miciek]

hi @pepegar, @antonkulaga. I will try to take over this one. Will keep you posted.

[pepegar]

Thanks @miciek!