Add preliminary support for rp strategies

Adds seperate rp function pointers for both vectorized and point-wise
handling of the Riemann solver routines.  Bug in the vectorized solver
is only real problem so far.  Maybe a memory issue.
Debug of limiter functions

It appears that limiters are not being applied to waves.  Turns out that
the limiter routine is no receiving proper waves, proably a function
interface problem.  Currently turning on high order corrections with and
without limiters gives the same result.
Minor additions and improvements