sty: single line for imports
provide examples
db arg now has default value of NULL

* this is more convenient when calling from other functions
add explicit db argument
clarify extrafun args
teach nlscan to work directly with neuronlists

* adjust examples accordingly
Run one nlscan example
fix bug in nlscan when wait=F
Merge branch 'feature/nlscan'

* finalises #167
* feature/nlscan:
  fix bug in nlscan when wait=F
  Run one nlscan example
  teach nlscan to work directly with neuronlists
  clarify extrafun args
  add explicit db argument
  db arg now has default value of NULL
  provide examples
  sty: single line for imports