Remove dbcp from codebase (moved to separated repository)
Add type hint to some util function in jdbc.core ns.
Fix some typos and minor code style improvement.
Add parse-querystring function.
Remove deprecated jdbc.pool ns.
Improve url->dbspec parsing.
Minor improvements on human friendly dbspec parsing.
Minor code reorganization.
Remove c3p0 code from codebase.
Set new versions of connection pool extensions.