log_run now saves the parameters

- saving the parameters and the config files in a tar.gz file along with
  the data
- reviewed what topics are skipped
Merge branch 'master' of https://github.com/StanfordDrivingTeam/driving_public
Added start time to log readers

for bag files: directly opening at the right location. For dgc files,
reading data until we get to the right point, which is less efficient.

also replaced all double time occurences with ros::Time