Crude workaround for pylint breakage

The way we currently call pylint, the exact order it inspect modules in
lib/http/ depends on the filesystem order. This is not good, and if
lib/http/server.py is loaded before lib/http/__init__.py, it will throw
a "R0921:763:HttpMessageReader: Abstract class not referenced" (as that
class is used in server.py).

For the short-term fix, we just add server.py after "ganeti", so that
it gets parsed (again?) and pylint sees the usage of the class.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>