Add helper functions to interactively setup SQL connection

[stardiviner]

Hope ejc-sql can create a universal helper function to help user setup SQL connection interactively.

For example, a command ejc-sql-connect-to-sql,

1. it will show the stored connections in persistent when no input yet.
2. After user input some characters like sqlite
3. if has match connection, then select it to connect.
4. if has no match connection, then create a new connect with the inputted string.
5. then interactively prompt user to input parameters of the connection, even auto show the available SQL JDBC drivers in available possible paths like ~/.m2/.

[kostafey]

Note: related pull request #84 (rejected but contains useful conversation).

[kostafey]

@stardiviner, Ok looks like the feature is implemented.
See description in README: https://github.com/kostafey/ejc-sql#create-connections-interactively
I hope that the creation process is simple enough that the user can be not familiar with Java & JDBC to configure a connection. The required JDBC driver will be automatically resolved and downloaded (if not yet) for the selected database type. Manual installation is not required for interactive-configured connections.

[stardiviner]

This is awesome!!! Thanks @kostafey. Much better than my simple and rough implementation.