Add interactive behavior to search commands

[satazor]

As suggested by @sindresorhus it would be cool if we could do multiple searches and navigate in the search results interactively. Perhaps we could use https://github.com/SBoudrias/Inquirer.js/ or a lower level library to do this.

[flesch]

I don't know exactly what @sindresorhus suggested, but it would be cool to combine searching with something like trymodule. Search for a package, and then load it into a REPL to test it out.

[rickycodes]

https://github.com/dthree/vorpal looks promising for this as well; also has a similar api to yargs with command.description, command.alias...