Sanitize some include headers

Sanitize some include headers

readinp.h was being used to acquire dependencies transitively, and was
being used where not required. Used some forward declarations where
suitable. Removed some C-style typedef struct to help with that.

This should help speed up compilation while doing some clean up I am
considering.

Change-Id: Iee7f0e523fdcc4c12d2a6a6e375b6739f63e65c5