Start work on adding unit tests to our cli code in order to have to
write less costly integration test.
Signed-off-by: Vincent Demeester <vincent@sbr.pm>
In file `api/types/client.go`, some of the "*Options{}" structs own a
`Filters` field while some else have the name of `Filter`, this commit
will rename all `Filter` to `Filters` for consistency. Also `Filters`
is consistent with API with format `/xxx?filters=xxx`, that's why
`Filters` is the right name.
Signed-off-by: Zhang Wei <zhangwei555@huawei.com>