This is an attempt to make clsql threadsafe by
- making threads own (via checkin, checkout during connect/disconnect) a database. Use of a database by a non-owner thread is an error.
- putting a DATABASE-DESC object into the VIEW-DATABASE slot of a db object, and using this to find a thread-appropriate database, rather than risking a collision between use of a VIEW-DATABASE by one thread and the same database in another thread
- fix some mysql issues, including library initialization, per thread inits, and sigpipe restoration
- put locking around caches and recording, and put caches and recorders into the DATABASE-DESC
Much more detail given in the text file below.