* Set BIGDL_IMPORT_IPEX default to true, i.e., auto import IPEX for XPU. * Remove import intel_extension_for_pytorch as ipex from GPU example. * Add support for bigdl-core-xe-21.
* Support deepspeed * add test script * refactor convert * refine example * refine * refine example * fix style * refine example and adapte latest ipex * fix style