Add support for LongColumn
make tests pass
make valueType configurable
return correct valueType
Revert "return correct valueType"

This reverts commit 0b42ca4c75a451e221bf74d312693f9eead9f945.
Revert "make valueType configurable"

This reverts commit 6f60a3f60437ddfff2065110d8622ef218fd4b65.
review comments - cleanup ColumnSelectorFactory
initial attempt for abstraction; druid cluster works with Derby as a default
try to make javadoc happy
attempted to fix merge-conflicts
second attempt to fix merge-conflicts
trying to revert files that have overwritten changes
finished merging into druid-0.7.x; derby not working (to be fixed)
derby seems to be working..?
Merge branch 'druid-0.7.x' of github.com:metamx/druid into jisoo-metadata
added MetadataSegmentManagerTest
added two seperate modules for mysql and postgres
cleaned up the code
review comments
fixed javadoc; fixed pom files; deleted unnecessary class