Predictable behaviour of `max_examples_limit` option

[tom-lord]

Ideally, Regexp#examples should always return up to max_results_limit.

Currently, it usually "aborts" before this limit is reached. (I.e. the exact number of examples generated can be hard to predict, for complex patterns.)

An enhancement would be to modify the algorithm such that results are always generated up to max_results_limit if possible.