Start tidyverse migration

Change-Id: Ifc972de789c22e2ff43159740d7f1fa7125e1ef2
diff --git a/NAMESPACE b/NAMESPACE
index 58e75e0..3074a48 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -1,9 +1,17 @@
 # Generated by roxygen2: do not edit by hand
 
 S3method(format,KorAPQuery)
+export("%>%")
+export(complete)
+export(group_by)
+export(mutate)
+export(select)
+export(summarise)
+export(year)
 exportClasses(KorAPConnection)
 exportClasses(KorAPCorpusStats)
 exportClasses(KorAPQuery)
+exportMethods(apiCall)
 exportMethods(clearCache)
 exportMethods(corpusQuery)
 exportMethods(corpusStats)
@@ -13,7 +21,17 @@
 exportMethods(initialize)
 exportMethods(show)
 import(R.cache)
+import(dplyr)
 import(httr)
-import(jsonlite)
 import(methods)
+import(purrr)
+import(tidyr)
 import(utils)
+importFrom(dplyr,group_by)
+importFrom(dplyr,mutate)
+importFrom(dplyr,select)
+importFrom(dplyr,summarise)
+importFrom(jsonlite,fromJSON)
+importFrom(lubridate,year)
+importFrom(magrittr,"%>%")
+importFrom(tidyr,complete)