initial rough pass for a stored token implementation

controller/store/sql/postgresql/005_v0_3_0_invites.sql

@@ -0,0 +1,16 @@
+-- +migrate Up
+
+--
+-- invites
+---
+
+create table invites (
+  id                    serial              primary key,
+  token                 varchar(32)         not null unique,
+  token_status          varchar(1024)       not null unique,
+  created_at            timestamp           not null default(current_timestamp),
+  updated_at            timestamp           not null default(current_timestamp),
+
+  constraint chk_token check(token <> ''),
+  constraint chk_status check(token_status <> '')
+);