Doris BE development and debugging environment construction
Add installation under ubuntu, dependent installation
Compile on ubuntu 20.04 physical machine, the actual test needs to install these dependencies:
autoconf automake libtool autopoint
* Update fe-idea-dev.md
use `brew install thrift@0.9` to install thrift 0.9.3.1
`brew edit thrift090 | head` shows thrift@0.9 uses thrift 0.9.3.1
* [Refactor] Remove the unnecessary if statement
Future<?> submit(Runnable task)
Submits a Runnable task for execution and returns a Future representing that task. The Future's get method will return null upon successful completion.
