add parse_state_interface_descriptions and parse_command_interface_description and reuse components

[saikishor]

As we discussed in yesterday's WG meeting, as the #1688 is merged, we would like to modify the import_state_interface_descriptions and import_command_interface_descriptions instead of parsing the hardware info to them, we parse the hardware_info_.joints and hardware_info_.sensors and it imports accordingly etc

Fixes: #1766

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.18%. Comparing base (ce5c35a) to head (b3ea566).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1768      +/-   ##
==========================================
- Coverage   87.19%   87.18%   -0.01%     
==========================================
  Files         118      118              
  Lines       11369    11355      -14     
  Branches     1049     1045       -4     
==========================================
- Hits         9913     9900      -13     
  Misses       1094     1094              
+ Partials      362      361       -1     

Flag	Coverage Δ
unittests	87.18% <100.00%> (-0.01%)	⬇️

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

Files with missing lines	Coverage Δ
.../include/hardware_interface/actuator_interface.hpp	93.50% <100.00%> (-0.62%)	⬇️
...ce/include/hardware_interface/sensor_interface.hpp	93.18% <100.00%> (-0.57%)	⬇️
...ce/include/hardware_interface/system_interface.hpp	87.23% <100.00%> (-0.73%)	⬇️
hardware_interface/src/component_parser.cpp	94.60% <100.00%> (+0.17%)	⬆️

[christophfroehlich]

LGTM