Add more build tool support!

[leaxoy]

This a great tool, it's so light but powerful. And a lot time it can replace eclipse and intellij idea.
But now it's only support maven and basic java project.
Is there any possible add other build tool support, like gradle, ant, ivy and so on.
In fact, a lot of project use maven build. But some are not.(zookeeper for example).

In the mean while, gradle became more and more popular among people.New project, android project, spring framework all use gradle as build tool.

So add other build tool support maybe great, and earn more users.

[fbricon]

Closing as duplicate of #10