adds server to serve the static files, fixes db tables

lootalot_db/migrations/2019-06-10-123922_create_items/up.sql

@@ -1,5 +1,5 @@
 CREATE TABLE items (
-  id INTEGER PRIMARY KEY,
+  id INTEGER PRIMARY KEY NOT NULL,
   name VARCHAR NOT NULL,
   base_price INTEGER NOT NULL
 );

lootalot_db/migrations/2019-06-10-123940_create_players/up.sql

@@ -1,9 +1,9 @@
 CREATE TABLE players (
-  id INTEGER PRIMARY KEY,
+  id INTEGER PRIMARY KEY NOT NULL,
   name VARCHAR NOT NULL,
-  debt INTEGER DEFAULT 0, -- debt to the group in copper pieces
-  cp INTEGER DEFAULT 0,
-  sp INTEGER DEFAULT 0,
-  gp INTEGER DEFAULT 0,
-  pp INTEGER DEFAULT 0
+  debt INTEGER DEFAULT 0 NOT NULL, -- debt to the group in copper pieces
+  cp INTEGER DEFAULT 0 NOT NULL,
+  sp INTEGER DEFAULT 0 NOT NULL,
+  gp INTEGER DEFAULT 0 NOT NULL,
+  pp INTEGER DEFAULT 0 NOT NULL
 );

lootalot_db/migrations/2019-06-10-124013_create_looted/up.sql

@@ -1,8 +1,8 @@
 CREATE TABLE looted (
-  id INTEGER PRIMARY KEY,
+  id INTEGER PRIMARY KEY NOT NULL,
   player_id INTEGER NOT NULL,
   item_id INTEGER NOT NULL,
-  acquired_date DATE DEFAULT NOW,
+  acquired_date DATE NOT NULL,
   FOREIGN KEY (player_id) REFERENCES players(id),
   FOREIGN KEY (item_id) REFERENCES items(id)
 );