Add function frequencyQuery (corpusQuery + corpusStats + ci)

Change-Id: Icb7ed900ea588f606a812d1e3122867a81cefaa2
diff --git a/NAMESPACE b/NAMESPACE
index a34e671..091ce17 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -23,6 +23,7 @@
 exportMethods(fetchAll)
 exportMethods(fetchNext)
 exportMethods(fetchRest)
+exportMethods(frequencyQuery)
 exportMethods(initialize)
 exportMethods(show)
 import(R.cache)
@@ -44,6 +45,7 @@
 importFrom(magrittr,"%>%")
 importFrom(stats,prop.test)
 importFrom(tibble,as_tibble)
+importFrom(tibble,remove_rownames)
 importFrom(tibble,rownames_to_column)
 importFrom(tidyr,complete)
 importFrom(tidyr,expand_grid)