error in prior for vecBdev in Stan code

[mdscheuerell]

There is an error in the specification of the prior for vecBdev. It is intended to be the process error for the RW on B, but the specification on line 31 limits it to the interval [0,1] instead of [-c,c] as on line 101. This won't affect models with time-invariant B, though.

[mdscheuerell]

Let's try the approach where we constrain any parameter(s), if desired, via lower/upper limits in the transformed parameters block, rather than do a stretch/shrink on line 72.