* script: record meta info into all bags.

* planning: add a gflag to protect nudge slowdown behavior.

* planning: reduce traffic light stop distance to 0.2 m

* planning: reduce minimum follow distance to 2m

* tools: set the default

line swing.

Planning: shortened the minimum follow distance from 10 to 5 (meter) to avoid to slow response when waiting left turn.

planning: reduce reference line length based on ADC speed and skip ST calculation for out of range obstacles.

Planning: (1) fixed turn signal bug. Localization: (2) fixed wrong order initilized variables. (#1800)

planning: enable prioritize_change_lane and add min change lane length check for short-cut change lane decision.

Planning: re-align time of each trajectory point so that we can use the publishing time as the timestamp for planning module -- In this way, every modules in Apollo has a consistent way in defining 'timestamp' in header.

* Planning: used more accurate vehicle state at current timestamp in planning.

* Planning: fixed broken tests.

* handle the case that reference line generation failed or too slow

* prepare for stitching reference line

planning: add min following time requirement to avoid following cross lane traffic. Stop for CROSS st region obstacle.