remove some references to unused objects from lalapps inspiral codes

this contains three patches to perform some housekeeping in lalapps/src/inspiral and lalapps/src/ring. A number of unused #include's are removed, references to a redundant function in lalinspiral are removed, and references to an unused structure type are removed. this is a prelude to a patch that will remove a large volume of obsolete, abandoned, code from lalinspiral, but I'm supplying this as a separate merge request so that it can be considered separately, and reverted separately if the affected developers ever wish to.