models: Add long_term_idle/last_active_message_id to UserProfile.

In this commit we are adding two new fields to the UserProfile
table. These fields are the:
long_term_idle: For storing a bool value representing status of user
being online in long time where 'long' will have a specific
definition.
last_active_message_id: For storing the message id which was last
updated into the UserMessage table for a particular user.

zerver/migrations/0089_auto_20170710_1353.py

@@ -0,0 +1,25 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.2 on 2017-07-10 13:53
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('zerver', '0088_remove_referral_and_invites'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='userprofile',
+            name='last_active_message_id',
+            field=models.IntegerField(null=True),
+        ),
+        migrations.AddField(
+            model_name='userprofile',
+            name='long_term_idle',
+            field=models.BooleanField(db_index=True, default=False),
+        ),
+    ]

zerver/models.py

@@ -561,6 +561,7 @@ class UserProfile(ModelReprMixin, AbstractBaseUser, PermissionsMixin):
     date_joined = models.DateTimeField(default=timezone_now) # type: datetime.datetime
     is_mirror_dummy = models.BooleanField(default=False) # type: bool
     bot_owner = models.ForeignKey('self', null=True, on_delete=models.SET_NULL) # type: Optional[UserProfile]
+    long_term_idle = models.BooleanField(default=False, db_index=True)  # type: bool
 
     USERNAME_FIELD = 'email'
     MAX_NAME_LENGTH = 100
@@ -577,6 +578,7 @@ class UserProfile(ModelReprMixin, AbstractBaseUser, PermissionsMixin):
     realm = models.ForeignKey(Realm, on_delete=CASCADE) # type: Realm
     api_key = models.CharField(max_length=API_KEY_LENGTH) # type: Text
     tos_version = models.CharField(null=True, max_length=10) # type: Optional[Text]
+    last_active_message_id = models.IntegerField(null=True)  # type: int
 
     ### Notifications settings. ###