This patch adds instance parameter fields to the Haskell instance
queries. The fields retrieve maps of parameters related to e.g.
hypervisors, or operating systems.
Every instance can have parameters different from the defaults,
and the fields allow for retrieving changes, defaults, and the
complete parameters.
To achieve this, some constants were converted from being
Python- to Haskell-generated.

Signed-off-by: Hrvoje Ribicic <riba@google.com>
Reviewed-by: Jose A. Lopes <jabolopes@google.com>