Use custom string struct to store line endings (wikitext, bf8a30f)

Created 2/9/2008, updated 3/5/2024

snippets

This shaves off a sliver of time on longer inputs because it allows us to replace a number of calls to rb_str_append with the more efficient rb_str_cat.

Before:

longer slab of ASCII text 13.510000 0.060000

After:

longer slab of ASCII text 13.450000 0.050000

Signed-off-by: Greg Hurrell <greg@hurrell.net>