send the whole request at once, even though the Expect: header was disabled
by the application. An effect of this change is also that small (< 1024
bytes) POSTs are now always sent without Expect: header since we deem it
more costly to bother about that than the risk that we send the data in
vain.
A) Normal non-proxy HTTP:
- no more "Pragma: no-cache" (this only makes sense to proxies)
B) Non-CONNECT HTTP request over proxy:
- "Pragma: no-cache" is used (like before)
- "Proxy-Connection: Keep-alive" (for older style 1.0-proxies)
C) CONNECT HTTP request over proxy:
- "Host: [name]:[port]"
- "Proxy-Connection: Keep-alive"
