add FlatDhcpUpgradeExtension

fix hostname for flat network provider when creating vm

upgrade agent version to 1.0

don't delete ceph pool by default when deleting the ceph primary storage

fix unit test

fix NPE when querying a null field

fix NPE when querying a null field

fix NPE when querying a null field

change version to 0.7.0

https://github.com/zstackorg/zstack/issues/15

Uable to start EIP VM after the host running virtual router VM reboots zstackio#15