Some error message for length violations are wrong

### Environment

* Python version: 3.10.6
* PyKwalify version: 1.8.0 (but still in master)

### Steps to Reproduce

1. Look at lines https://github.com/Grokzen/pykwalify/blob/master/pykwalify/core.py#L892 and https://github.com/Grokzen/pykwalify/blob/master/pykwalify/core.py#L910
2. Realize that the wording should be "less than"/"less than or equal to" rather than "greater than" for violations of `min` and `min-ex`, and "greater than or equal to" for "max ex".

### Expected Behavior

- I expect to error messages to be correct.

### Observed Behavior

- They include "greater than" for `min` and `min-ex` violations, while this is actually expected behaviour 🙂.