Updating projects version to 0.7.0-incubating-SNAPSHOT.

The following pull requests have been either been merged or closed as of this release.

closes #1  (via 207f2e4)
closes #3  (*No longer relevant*)
closes #8  (via cb3132a)
closes #11 (via 727adb7, a73512d)
closes #12 (*Issue fixed via DRILL-88*)
closes #13 (*Closed as Won't Fix*)
closes #14 (via f0be80d)
closes #17 (via a38856c)
closes #35 (via 741aab0)
closes #60 (via 1648195)
closes #64 (Resolved as part of other function merges)
closes #65 (via 28dd76a)
closes #66 (via 4862b2b)
closes #67 (via 2ca9c90)
Setting to SNAPSHOT version, (missed while collecting the stale PRs)
Adding my public key.
DRILL-1505: Updating Session Value Doesn't Reflect In 'sys.options' Query Output
DRILL-1494: Fix annoying and unnecessary warning 'Failure while trying to load .drill file'
DRILL-1495: Test cases should log relevant message in case of expected failures
DRILL-1485: tools/verify_release.sh does not have execute permission bit set
DRILL-1409: DbVisualizer fails to connect to Drill using embedded jdbc driver
DRILL-1497: Fix test failure in o.a.drill.jdbc.test.TestMetadataDDL
DRILL-1490: Upgrade to ProGaurd 5.0
DRILL-1493: Upgrade ASM to 5.0
DRILL-1492: Update readme with supported versions of Java

* Keeping the supported Java version to 7 until we get all issues around Java 8 resolved.
DRILL-1516: When searching for the java executable, ignore directories named "java"