Significant updates to meta command handling, including improved help / support as well as a massive retooling of how drivers are built/supported.

• .usqlrc support
• Now prompts for a password on connect, as well as psql compatible -w and -W cli options
• \i and \ir and their \include and \include_relative variant meta commands have been fixed
• Better meta command help
• Issues with database URLs fixed
• Output issues on Windows fixed
• Standardized/better driver error messages
• Additional psql compatibility command line options, meta commands
• Drivers can now be included using go build -tags <driver> or, alternatively, excluded using go build -tags no_<driver>
• Additional build tags all and most added (most is same as all, but excludes the cgo drivers odbc and oracle)