Selectively deploy submodule into maven repository

Until now, Zeppelin deployed all it's submodule into maven repository.
Tough not all submodule need to be in maven.

This PR disables some submodule that does not need to be in maven repository.

Disabled submodule

- zeppelin-server
- zeppelin-docs
- zeppelin-web
- zeppelin-distribution
- spark
- markdown
- shell

Enabled submodule
- zeppelin-zengine (to develop custom interpreter)