* [common] Make dolphinscheduler_env.sh work
* Change dist tarball `dolphinscheduler_env.sh` location
from `bin/` to `conf/`, which users could finish their
change configuration operation in one single directory.
and we only need to add `$DOLPHINSCHEDULER_HOME/conf`
when we start our sever instead of adding both
`$DOLPHINSCHEDULER_HOME/conf` and `$DOLPHINSCHEDULER_HOME/bin`
* Change the `start.sh`'s path of `dolphinscheduler_env.sh`
* Change the setting order of `dolphinscheduler_env.sh`
* `bin/env/dolphinscheduler_env.sh` will overwrite the `<server>/conf/dolphinscheduler_env.sh`
when start the server using `bin/dolphinsceduler_daemon.sh` or `bin/install.sh`
* Change the related docs
Currently the size of our distribute package is up to
800MB, this patch is migrate python gateway server into
api server
The distribute package size before and after this patch is:
```sh
# before
796M apache-dolphinscheduler-2.0.4-SNAPSHOT-bin.tar.gz
# after
647M apache-dolphinscheduler-2.0.4-SNAPSHOT-bin.tar.gz
```
kezhenxu94
xiangzihao
Jiajie Zhong
Paul Zhang
caishunfeng