Refactor: Trajectory loading seperated into external function

[onurtore]

Utilizes additional function to load actor trajectories.

[codecov[bot]]

Codecov Report

Merging #1572 (224598e) into ign-gazebo6 (8c9489d) will increase coverage by 0.00%. The diff coverage is 68.75%.

@@             Coverage Diff              @@
##           ign-gazebo6    #1572   +/-   ##
============================================
  Coverage        64.40%   64.41%           
============================================
  Files              320      320           
  Lines            25892    25894    +2     
============================================
+ Hits             16677    16680    +3     
+ Misses            9215     9214    -1     

Impacted Files	Coverage Δ
src/rendering/SceneManager.cc	28.87% <68.75%> (+0.20%)	:arrow_up:

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[onurtore]

Commits done by Github Interface fails to comply DCO. Should I update them?

[onurtore]

@ahcorde Friendly ping

[onurtore]

DCO failing. I tried to rebase but ended up with many conflicts which are not related to this PR. It fails because of merge without of a sign.

[ahcorde]

@osrf-jenkins run tests please!