Support retrying QUAD_GANTRY_LEVEL a configurable number of times
to a configurable tolerance both in the config or as parameters.
- By default keeps original behavior of no retries.
- Adds parameters RETRIES and RETRY_TOLERANCE to QUAD_GANTRY_LEVEL gcode.
- adds config options retries and retry_tolerance to `[quad_gantry_level]`
- issues an error if we are getting worse intead of approaching tolerance
- issues an error if retries were requested but we did not reach the tolerance
in the specified number of retries
Signed-off-by: John "Fess" Fessenden <fess@fess.org>
bd40690bd1