[JTC] Cleanup includes

[christophfroehlich]

I cleaned-up the includes. It compiles and linters do not complain.

Fixes some items of #944

• I tried to not to rely on transitive inclusion of header files
• I removed forward declarations, but maybe we could let the fwd declaration of the project-intern Trajectory class?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (3c3f614) 46.86% compared to head (7adf3ab) 46.86%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #943   +/-   ##
=======================================
  Coverage   46.86%   46.86%           
=======================================
  Files          41       41           
  Lines        3862     3862           
  Branches     1816     1816           
=======================================
  Hits         1810     1810           
  Misses        792      792           
  Partials     1260     1260           

Flag	Coverage Δ
unittests	46.86% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
...jectory_controller/joint_trajectory_controller.hpp	0.00% <ø> (ø)
...include/joint_trajectory_controller/tolerances.hpp	55.00% <ø> (ø)
...ory_controller/src/joint_trajectory_controller.cpp	48.54% <ø> (ø)

[bmagyar]

Thank you, this is a good idea!

[bmagyar]

I bet some of these come from older cppcheck errors, let's see how the backports will do! :D