core: Always refresh authorization when creating streams

Non-resumable upload streams quite often fail with authorization errors as we are probably hitting some limits. The only way currently to deal with them is to refresh authorization manually and upload everything again as it is not possible to resume the transfer. This is big issue for streaming operations provided by GVfs. I have made several tests and realized that if we explicitely refresh the authorization before the transfer, then those authorization errors doesn't occur. So let's always refresh the authorization when constructing the streams and do the same for upload streams as well as they are also affected. In theory, the resumable streams could solve this better, however they currently require content size to be specified at the beginning, which is not usable for the streaming operations in GVfs.

Fixes: #23 (closed)