Limit amount of matches during replacement

[ghost]

The buffer passed to the replace function can be bigger than the original match
and cause extra matches to occur during replacement. This adds an extra replace
function that doesn't allow matches beyond the original range to get replaced.

I've added replace_with_captures_in_range to do this, but I'm not sure if this should be fixed within
replace_with_captures_at itself (as that one isn't always used with a range).

Fixes #2095

[ghost]

Resolved by #2209

[BurntSushi]

Ah I missed this PR! Thanks. I did end up taking a slight different approach by writing the new function as a new internal helper routine instead of making it a new public API in grep-matcher. Probably grep-matcher should evolve its *_at APIs to accept ranges instead of just the starting location. But that's a battle for another day.