Streamline LAPPD inclusion

[marc1uk]

Right now the code is littered with if (isPMT){ ... } else if(isLAPPD) { ... } statements.
In nearly all of these cases the code executed in each case is virtually identical, differing only by the use of LAPPD variables that are clones of equivalent PMT variables.
The existing support for multiple PMT types could natively handle LAPPDs in the majority of these cases, removing the duplicated code.