TF-48 Setup database manager for local data

core/lib/data/local/config/database_config.dart

@@ -0,0 +1,5 @@
+
+class DatabaseConfig {
+  static final String databaseName = 'TMailDatabase.db';
+  static final int databaseVersion = 1;
+}

core/lib/data/local/config/email_address_table.dart

@@ -0,0 +1,12 @@
+
+class EmailAddressTable {
+  static const String TABLE_NAME = 'EmailAddress';
+
+  static const String EMAIL = 'email';
+  static const String NAME = 'name';
+
+  static const String CREATE = '''CREATE TABLE IF NOT EXISTS $TABLE_NAME (
+    $EMAIL TEXT PRIMARY KEY,
+    $NAME TEXT
+  )''';
+}