add perception obstacle message publish interface, and modify hdmap interface in the module of perception (#218)

* add pcl_util

* add perception common lib files

* add lidar_process, and modify code style

* add perception obstacle message publish interface

* modify hdmap interface, but it is commented out until the map module is ready

separate data producer and consumer.

* fixed minor issues.

* fixed apollo::planning::TrajectoryPoint issues. DO NOT KNOWN why it can still be compiled before...

* fixed reference line constructor.

* use std::string as ObjectId
* remove LRUCache

fixed apollo::planning::TrajectoryPoint issues. DO NOT KNOWN why it can still be compiled before... (#232)

fixed apollo::planning::TrajectoryPoint issues.

move namespace-level template functions to class-level overloaded functions so that class members can be accessed (#229)