Don't try to define fout in Global workspace to fix missing file error in call to NeuropilStats

* fout is an internal variable inside NeuropilStats()
* this definition will be ignored by NeuropilStats and would not have be correct anyway 
  (it should be a path to a file ending in .rds not a directory)
The D. yakuba calculation of jacobians should use the melanogaster mask

* since a successful D. yakuba template was never obtained
  so in the end you used the D. melanogaster FBIS1 template
Don't redefine leaconfig$Dmel$IS1.4um to point to a Dyak brain

* leaconfig$Dyak$IS1.4um will never be used (because the Dyak template creation failed)
  but this is better than redefining the leaconfig$Dmel$IS1.4um to point to a non-existent
  Dyak brain.