Make service/generator/jive-sdk.js autogen the valid options (they're hard coded now)

[rachoac]

var validTypes = ['all', 'activity', 'tile', 'example' ];
var validCommands = ['create','help'];
var validTileStyles = ['list', 'gauge', 'table' ];
var validExamples = ['bitcoin'];

All those values need to be introspected from the directories under service/generator/template

[rachoac]

fixed