Fix "unhandled case in switch" warning
Add cases for uname() for all known platforms

After what QEMU linux-user says about those.

Not sure what to do for ARM. I used the lowest emulated CPU in QEMU.
Fix type mismatch warnings
Add the port to the HTTP Host header when needed.

* When the port is not the default one, it must be added to the "Host"
header so the server knows what we're connecting to.

Fixes #11070.
Fix out-of-date comment.
Test for relative URL with a port in the base URL.

As expected, the port is preserved.
HttpRequest: more small fixes and cleanups

* Remove unneeded field fOutputHeaders and convert it to a local for the
only method that uses it,
* Don't return EOVERFLOW when flushing data from ZLib (the ZLib
decompressor returns this, but zlib docs states that this is NOT an
error condition).
* Replace unneeded temporary BNetBuffer of fixed size with BStackOrHeapArray.
Add packages for lame
webpositive: Officially handle gopher: URI scheme now

Avoids it asking Google what to do with the URL.