icu4c: add bottle regex.
mysql: update bottles.
icu4c 52.1

Closes #23188.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
icu4c: 52.1 bottles.
clipper 0.1 (new formula)

Clipper is an OSX launch agent that exposes the local clipboard to
processes running both locally and remotely.

This makes it useful for tools like `tmux`, as you can integrate `tmux`
with Clipper for seamless copy/pasting between a remote `tmux` instance
and your local clipboard.

More information and documentation can be found at:
https://github.com/wincent/clipper

Closes #23039.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>