This is useful for macros that'd like to skip QGL if already leveled,
e.g.:
```
{% if not printer.quad_gantry_level.applied %}
QUAD_GANTRY_LEVEL
{% endif %}
```
Signed-off-by: Michael Rose <elementation@gmail.com>
Move the reference of "printer" status fields from
Command_Templates.md to a new Status_Reference.md file.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>