There were several places where default sector and buffer sizes of 2048 were changed to DEFAULT_TASK_STACKSIZE. This is not correct. This was noted by Xiao Xiang.
This commit changes only ones with the default 2048 and
leaves the others.
E.g. this leaves SYSTEM_RAMTEST_STACKSIZE, whose default is 1024.
I guess those need to be inspected one-by-one.
Some improvements could be made by anyone. For example, I know the main routine in perform() shall be split into several parts for readability. I apologize in advance for this kind of spaghetti code, but I was short on time to refactor it. Also chunked HTTP transfer encoding would be a nice contribution from anyone interested. It is detected but not yet supported.