configfile: Add get_status() to export raw config file information

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

docs/Command_Templates.md

@@ -180,6 +180,12 @@ The following are common printer attributes:
   QUERY_ENDSTOP command. Note, due to the order of template expansion
   (see above), the QUERY_STATUS command must be run prior to the macro
   containing this reference.
+- `printer.configfile.config["<section>"]["<option>"]`: Returns the
+  given config file setting as read by Klipper during the last
+  software start or restart. (Any settings changed at run-time will
+  not be reflected here.) All values are returned as strings (if math
+  is to be performed on the value then it must be converted to a
+  Python number).
 
 The above list is subject to change - if using an attribute be sure to
 review the [Config Changes document](Config_Changes.md) when upgrading