Combine datasource and columnar core jar

[zhouyuan]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
We use to maintain two jars for data source and engine core, mainly due to these two are separated projects in OAP 1.1.
As these two were merged into one project, it's not necessary to maintain two separate jars, a big fat jar should be enough - it also reduce the complexity on releasing and spark configuration.

Describe the solution you'd like
combine these two jars into one

Describe alternatives you've considered
N/A

Additional context
N/A

[PHILO-HE]

Fixed.