one cannot put multiple particle MCMC samplers in an MCMC

[paciorek]

1. if one tries to use the same type of filter multiple times, one gets this error:

Error in nimbleProject$instantiateCmodelValues(thisObj, dll) :
  Trying to instantiate a modelValues type that the project has no record of. Try setting option resetFunctions = TRUE in compileNimble

2. if one tries to use distinct PF types for different samplers in an MCMC, one gets this:

Error: Not all elements in the fun list for compileNimbleFunction are specialized from the same nimbleFunction.  The generator names include: buildBootstrapFilter buildAuxiliaryFilter

As a side note, Perry suggested this work-around: "Provide a cleverly built "filterType" function that creates the filter object once and then returns the same object if called repeatedly. That way there would be only one filter object."