'maptools' will be retired by the end of 2023,

[raerickson]

Hi, I see that Maptools will be retired. How hard would it be for me to remove this dependency from your package?

> library(legendMap) ## Used for north arrow and distance key
Loading required package: maptools
Loading required package: sp
Checking rgeos availability: FALSE
Please note that 'maptools' will be retired by the end of 2023,
plan transition at your earliest convenience;
some functionality will be moved to 'sp'.
 	Note: when rgeos is not available, polygon geometry 	computations in maptools depend on gpclib,
 	which has a restricted licence. It is disabled by default;
 	to enable gpclib, type gpclibPermit()
Loading required package: grid