set_crop_lims: set_crop_lims
In AndySouth/climcropr: Simple Crop Modelling at a Global Scale

create a crop object with specified limits to allow suitability modelling

1	set_crop_lims(GMIN, GMAX, KTMP = 0, TMIN, TMAX, RMIN, RMAX)

`GMIN`	minimum growth cycle in days
`GMAX`	maximum growth cycle in days
`KTMP`	killing temperature degrees C
`TMIN`	min temperature degrees C
`TMAX`	max temperature degrees C
`RMIN`	min rainfall needed in growth cycle mm
`RMAX`	max rainfall tolerated in growth cycle mm

made_up_crop <- set_crop_lims(GMIN=90, GMAX=120, KTMP=0, TMIN=10, TMAX=35, RMIN=500, RMAX=2000)
#test running suitability for small area
#subset climate data to make faster run
st_clim2 <- raster::crop(st_clim, extent(-10,10,45,65))
rastsuit <- ecocrop_a_raster(made_up_crop, st_clim2, simpler=TRUE)