fix imports to prevent warning

warning appeared following update to struct package wrt .DollarNames implementation

Author: grlloyd

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: metabolomicsWorkbenchR
 Type: Package
 Title: Metabolomics Workbench in R
-Version: 1.3.0
+Version: 1.3.1
 Authors@R: c(
     person(
         c("Gavin","Rhys"),

NAMESPACE

@@ -21,5 +21,6 @@ import(httr)
 import(jsonlite)
 import(methods)
 import(struct)
-import(utils)
 importFrom(data.table,rbindlist)
+importFrom(utils,read.delim)
+importFrom(utils,read.table)

R/class_def.R

@@ -1,6 +1,6 @@
 #' @include generics.R parse_fcns.R
 #' @import methods
-#' @import utils
+#' @importFrom utils read.delim read.table
 
 ############################## BASE ##########################################
 mw_base = function(private,locked){