web/postkey/models.py: change type of "description" field

Now it limited to 4 KB.

web/postkey/models.py

@@ -5,7 +5,7 @@ class i2phost(models.Model):
 	name = models.CharField("I2P hostname", max_length=67, unique=True)
 	# Maximum key length 616 bytes (to account for certs up to 100 bytes).
 	b64hash = models.CharField("Base 64 hash", max_length=616)
-	description = models.TextField("Description", blank=True)
+	description = models.CharField("Description", max_length=4096, blank=True)
 	date_added = models.DateTimeField(auto_now_add=True)
 	# Last time this host was up
 	last_seen = models.DateTimeField(null=True)