File upload: Very bad WiFi connection causes upload failure and module hang

[nielsonm236]

Related to #171 and #173. While using a really bad WiFi connection and attempting ethernet upload of code to my test modules I encountered the old upload failure and hang issues. I looked into the code (again) and found a few locations where while() loops might not find their exit conditions if the arriving upload file was badly corrupted. I'm going to add a 60 second timeout to the code and more cleanly abort the process if the timeout occurs.