Changes in version 1.0.0.9007                      

  - dataPurification_SKPSP() now removes every measurement of a tree
    that died of a cause in codesToExclude; it stopped with an error
    before (#24).
  - getPSP() gains codesToExclude, damage agent codes to exclude by
    source (BC, AB, SK, NFI) (#24).
  - getPSP(forGMCS = TRUE) now removes BC trees damaged by mountain pine
    beetle: it passed the code "IMB", which matches no BC code, instead
    of "IBM" (#24).