Display Git commit info on command line


This is a first attempt at https://github.com/bigdatagenomics/adam/issues/41
(a “pick-me-up”).
To dump useful information while reporting bugs.


```
 $ java -jar adam-cli/target/adam-0.6.1-SNAPSHOT.jar buildinformation
Build information:
git.commit.id.abbrev: b476864
git.commit.message.full: Do code clean-up (BuildInformation)

git.commit.id: b476864265ee83660ea3cdb116241fb853720294
git.commit.message.short: Do code clean-up (BuildInformation)
git.commit.id.describe: adam-parent-0.6.0-69-gb476864
git.branch: git_properties
git.commit.time: 23.02.2014 @ 14:43:05 EST
git.remote.origin.url: git@github.com:bigdatagenomics/adam
git.build.time: 23.02.2014 @ 14:45:25 EST
```

It uses https://github.com/ktoso/maven-git-commit-id-plugin