Knows how to OAuth already.
This commit also adds CloudManager::addStorage(), so OneDriveStorage can
add newly created Storage and CloudManager can save it in the
configuration file.
It reads the passed NetworkReadStream and prints its contents onto
console (for now). It would be writing contents into file.
To simplify work with raw NetworkReadStream there is a new CurlRequest.
It basically does nothing, but as ConnMan handles transfers only if
there is an active Request, you need some Request to get
NetworkReadStream working. Thus, there is a CurlRequest, which is active
until NetworkReadStream is completely read. CurlRequest also has useful
addHeader() and addPostField() methods in order to customize the request
easily. Use execute() method to get its NetworkReadStream.
DropboxStorage implements streamFile() and download() API methods. As
DownloadRequest is incomplete, it is not actually downloading a file,
though.
Alexander Tkachev