TAJO-1590: Moving to JDK 7

[jinossy]

No description provided.

[jihoonson]

There are still some remaining configurations.

$ find . -name "pom.xml" -exec grep -H -n "1\.6" {} \;
./pom.xml:135:                <version>1.6</version>
./pom.xml:152:          <version>1.6</version>
./pom.xml:214:                    <versionRange>[1.6,)</versionRange>
./tajo-project/pom.xml:403:                <version>1.6</version>
./tajo-project/pom.xml:416:          <version>1.6</version>
./tajo-project/pom.xml:505:                    <versionRange>[1.6,)</versionRange>

[jinossy]

@jihoonson
I update the java version in enforcer plugin. but other result is maven-antrun-plugin version

[jihoonson]

Right. Thanks for fast update.
+1 ship it!