Make upload more fail resistent

[paule96]

Internet providers are complicated in special for mobile connections. Sometimes when they detect big file uploads they throttle the upload speed or let you request to wait a relatively long time. (more than a minute)
The problem this currently results in an unhandled exception in FileExchange (good thing is azcopy has the same problem, so we are not alone)

But it should be possible to find a way to workaround this. An Idea would be:

• detect the block, by catching the exception when a block failed to download (it's a timeout exception)
• if this happens wait 5mins
• after our threshold we continue the upload process

Note: Currently I only was finding this behavior for uploads. Downloads seems to be not affected in a way that break things.