Altered suggested packages to inc pkgdown

Author: waternumbers

DESCRIPTION

@@ -20,7 +20,7 @@ Description: This is a fast and flexible implementation of the Kalman
 License: GPL (>= 2)
 Encoding: UTF-8
 Imports: graphics
-Suggests: RUnit, knitr, rmarkdown, covr, bookdown
+Suggests: RUnit, knitr, rmarkdown, covr, pkgdown
 Depends: R(>= 2.8)
 BugReports: https://github.com/waternumbers/FKF/issues
 URL: https://waternumbers.github.io/FKF/, https://github.com/waternumbers/FKF