Release v0.017

This release fixes a bunch of issues with ysql, and allows displaying of database configuration.

Full changelog below:

• remove docs about trim option
• add validation for database driver (#76)
• add drivers ysql command to list database drivers (#75)
• document new ysql config read commands
• show error if a database key does not exist (#74)
• add read config commands to ysql (#73)
• add documentation for ymask (#53)
• make DBI completely optional (#77)
• add cookbook with embedded json recipe (#82)