add unexpectedAdmissionError as retryable failed reason (kubedl-io#225)

Signed-off-by: yyh <[email protected]>

Co-authored-by: yyh <[email protected]>

make 0.4.0 releases

Merge pull request kubedl-io#88 from tzzcfrank/group

release 0.3.0

Merge pull request kubedl-io#86 from tzzcfrank/0.2.0

release 0.2.0

Merge pull request kubedl-io#63 from QiJune/edl

elasticdljob: type definition and controller implementation of elasticdljob workload.