Thrift import, compiler warning, and timer cleanup
Call AbstractElement getID() insteado of getId()

Relying on capitalization significance to differentiate methods on
this object seems like asking for trouble.  For now, just fix the
capitalization bug introduced by
37b84fb6425485bd5f2ab0396885a9a9d616e47c, but we might want to
refactor getID() and getId() to more distinct names.
Cassandra-Thrift refactoring

This commit subsumes the useful changes in the thrift-refactoring
branch.  It's not a merge commit because titan03 and
thrift-refactoring had diverged enough to cause conflicts that seemed
to take longer to resolve than reproducing the changes on titan03.

This commit also updates to Apache commons-pool 1.6.  This
commons-pool version includes support for generics, obviating a bunch
of generics code formerly in
titan-cassandra/src/main/java/.../thrift/thriftpool.