Pull, push, build, logs are always streamed. Pull and push is decoded on the fly

This is a tentative fix for #255 and #102. This would be a breaking change since it gets read of the stream parameter for several methods, and changes the behavior for those who didn't use streaming.

@denibertovic @mpetazzoni @johncosta @discordianfish What do you think of this change? It makes the code simpler and fixes a few issues but it's a big API change nevertheless.