add_incursions: Add incursions to infectious line list
In mrajeev08/simrabid: Individual-based model of canine rabies

add_incursions adds incursions generated from incursion_fun function to the line list of infections.

add_incursions(
  cell_id_incs,
  cell_ids,
  ncells,
  admin_ids = NULL,
  row_ids,
  x_coord,
  y_coord,
  tstep,
  counter,
  days_in_step = 7
)

`cell_id_incs`	numeric vector, number of incursions to add to each grid cell, generated from `incursion_fun`
`cell_ids`	integer vector, of all possible cell_ids to match between cell & row_ids
`ncells`	integer, number of grid cells total in the raster of simulated space
`admin_ids`	integer vector, admin ids corresponding to the row_ids
`row_ids`	integer vector, row id of state matrix
`x_coord`	numeric vector of Eastings which correspond to the centroid of grid cells
`y_coord`	numeric vector of Northings which correspond to the centroid of grid cells
`tstep`	integer, the time in which the incursions are being added (i.e. the current time step)
`counter`	integer, the id number to start from to assign ids to the new incursions
`days_in_step`	integer, the number of days in each tstep, to assign the day of infectiousness to each incursion