Document password_cost_time_lastcheck in guiconfig

Changelog.md

@@ -6,6 +6,8 @@ This file holds the changelog for Pepperminty Wiki. This is the master list of t
 ## Changed
  - Password hashing has been overhauled! A totally new-and-different system is being used now, so you'll need to rehash all your passwords.
      - The `hash` action supports the new password hashing scheme.
+     - Added `password_cost`, `password_cost_time`, and `password_cost_time_interval` settings
+     - `password_cost` is recalculated automatically every week by default (it keeps track of this via the `password_cost_time_lastcheck` 'setting')
  - The `css` setting will now keep a value of auto, even when `peppermint.json` is automatically updated by _Pepperminty Wiki_.
 
 ## v0.16

peppermint.guiconfig.json

@@ -37,6 +37,7 @@
 	"password_cost": {"type": "number", "description": "The cost to use when hashing passwords.", "default": 12},
 	"password_cost_time": {"type": "number", "description": "The desired number of milliseconds to delay by when hashing passwords. Pepperminty Wiki will automatically update the value of password_cost to take the length of time specified here. If you're using PASSWORD_ARGON2I, then the auto-update will be disabled.", "default": 100},
 	"password_cost_time_interval": {"type": "number", "description": "The interval, in seconds, at which the password cost should be recalculated. Set to -1 to disable. Default: 1 week", "default": 604800},
+	"password_cost_time_lastcheck": {"type": "number", "description": "Pseudo-setting used to keep track of the last recalculation of password_cost. Is updated with the current unix timestamp every time password_cost is recalculated.", "default": 0},
 	"require_login_view": {"type": "checkbox", "description": "Whether to require that users login before they do anything else. Best used with the data_storage_dir option.", "default": false},
 	"data_storage_dir": {"type": "text", "description": "The directory in which to store all files, except the main index.php.", "default": "."},
 	"delayed_indexing_time": {"type": "number", "description": "The amount of time, in seconds, that pages should be blocked from being indexed by search engines after their last edit. Aka delayed indexing.", "default": 0},