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ARROW-4180: [Java] Make CI tests use logback.xml

- Add a logback.xml for each project with the default log level set to info.
- Set the "verbose" property for git-commit-plugin to false
- quieten output from qos.logback by attaching the NopStatusListener
- Fix a bunch of doc errors in ArrowBuf.java

Author: Pindikura Ravindra <ravindra@dremio.com>

Closes #3449 from pravindra/javalog and squashes the following commits:

d70649d <Pindikura Ravindra> ARROW-4180: Remove info level for maven (it's the default)
076fbd7 <Pindikura Ravindra> ARROW-4180: update README and add an appender
ea3674b <Pindikura Ravindra> ARROW-4180: restore travis.yaml, set info loglevel
c3fec21 <Pindikura Ravindra> ARROW-4180: Fix a typo in ci script
b567651 <Pindikura Ravindra> ARROW-4180: quieten output from logback
fc63176 <Pindikura Ravindra> ARROW-4180: add explicit logback.xml for each project
cc3d496 <Pindikura Ravindra> ARROW-4180:  Make CI tests use logback.xml