Added simple user auth

Fixes #14.

Change-Id: I748933214f43ac7298f1e93c14bb0ee881976d43

sql/init.sql

@@ -0,0 +1,18 @@
+CREATE TABLE users (
+    email TEXT PRIMARY KEY,
+    token TEXT UNIQUE,
+    registered boolean DEFAULT 0,
+    requested DATETIME
+);
+
+CREATE TABLE namespaces (
+    ns TEXT PRIMARY KEY,
+    email TEXT REFERENCES users(email) ON DELETE CASCADE
+);
+
+CREATE TABLE packages (
+    vcs TEXT,
+    repo TEXT,
+    path TEXT UNIQUE,
+    ns TEXT REFERENCES namespaces(ns) ON DELETE CASCADE
+);