bundle an older version of kirby toolkit, since the latest version completely breaks Chartridge

recent changes to kirby toolkit have changed how the toolkit works, and
as a result, Chartridge is extremely error-prone. the old version
(which Chartridge was developed under) does not have the same problems.
this also makes Chartridge more future-proof and easier to install.
fixed multiple bugs in boot.php

- now, it's okay if the database has already been created (but
Chartridge will still automatically create it if necessary)
- boot.php will no longer affect the existing structure of a database,
but it will still set up databases for use with Chartridge
- fixed a bug that could produce a PDOException
fixed checkpoint creation ui bug, added functionality to bonus creation