Add filter variables with dummy data (closes #40)
Add filter variables with dummy data (closes #40)

Details:
  * add commands and targets
  * add dummy functions: `integer_dummy()` and `spatial_dummy()`
  * update the data dictionary
  * set.seed for psuedo random numbers

tiernanmartin/home-and-hope,tiernanmartin/home-and-hope,tiernanmartin/home-and-hope