TAJO-814: Set up Travis CI builds.
Changed git depth.
Add script line.
set install true.
removed 'true'
Add travis-build.sh.
Improved yml and rename travis-build.sh.
Add path for protoc.
Fixed the bug which results in empty disk list.
Add rediction of protobuf compilation to /dev/null.
Add quite option to maven.
Changed some logs into debug level.
redirection from stdout to /dev/null.
Changed log4j for test and reduced logs.
Completed uniform splitter of multiple character range.
Merge branch 'master' of github.com:hyunsik/tajo into TAJO-966

Conflicts:
	.travis.yml
	CHANGES
	tajo-core/src/main/java/org/apache/tajo/engine/planner/rewrite/ProjectionPushDownRule.java
	tajo-core/src/main/java/org/apache/tajo/master/GlobalEngine.java