Add executor interface

repository/executor.go

@@ -0,0 +1,10 @@
+package repository
+
+import "database/sql"
+
+// executor allows for the execution of various database functions
+type executor interface {
+	Exec(query string, args ...interface{}) (sql.Result, error)
+	Query(query string, args ...interface{}) (*sql.Rows, error)
+	QueryRow(query string, args ...interface{}) *sql.Row
+}