Replace regexes by default, like grep, and like other replacement tools.
To treat patterns as text literals (the old behaviour), use the `--fixed-strings`/`-F` option.
The `--escape`/`-e` option is deprecated: it has an illogical name, since it *un*escapes the pattern, and it has little use (grep has no equivalent).
The formatting of the man page is fixed: no more paragraph break in the middle of the synopsis.
Feedback on this release is most welcome, both on the design and about any bugs I may have introduced.