Jiminy release 1.8.3

[duburcqa]

• [core] Make visual and collision models optional. ([core/python] Allow 'Model' instantiation from Python. #730)
• [core] Throw exception when trying to alter hardware or controller internals during simulation. ([core/python] Allow 'Model' instantiation from Python. #730)
• [core] Mark src-local functions as static. ([core/python] Allow 'Model' instantiation from Python. #730)
• [core] Add some missing bad control flow checks. ([core/python] Allow 'Model' instantiation from Python. #730)
• [core] Print warnings even for release build type. ([gym/envs] Fix broken 'Ant' environment. #731)
• [core] Fix broken 'getRigidVelocityFromFlexible'. ([gym/common] Add 'DeformationEstimator' block. #732)
• [core/python] 'Model' can now be instantiated from Python. ([core/python] Allow 'Model' instantiation from Python. #730)
• [core/python] Fix partially broken 'FunctionalController' bindings. ([core/python] Allow 'Model' instantiation from Python. #730)
• [core/python] Avoid visitor pattern when irrelevant. ([core/python] Allow 'Model' instantiation from Python. #730)
• [core/python] Expose more methods for 'Model'. ([gym/envs] Fix broken 'Ant' environment. #731)
• [core/python] Fix multiple typos. ([gym/envs] Fix broken 'Ant' environment. #731)
• [python/simulator] Fix 'robot' and 'robot_state' corrupted if robot is replaced. ([gym/envs] Fix broken 'Ant' environment. #731)
• [gym/common] Add 'compute_tilt_from_quat', 'swing_from_vector', and 'remove_twist_from_quat'. ([gym/envs] Fix broken 'Ant' environment. #731)
• [gym/common] Fix 'refresh_observation' being called before 'initialize_buffers' at simulation start. ([gym/envs] Fix broken 'Ant' environment. #731)
• [gym/common] Fix broken mahony filter for 'twist_time_constant != None'. ([gym/envs] Fix broken 'Ant' environment. #731)
• [gym/common] Fix support of non-batched mode for generic math. ([gym/envs] Fix broken 'Ant' environment. #731)
• [gym/common] Fix 'matrix_to_rpy' to be consistent with 'pin.matrixToRpy'. ([gym/envs] Fix broken 'Ant' environment. #731)
• [gym/common] Add 'DeformationEstimator' block. ([gym/common] Add 'DeformationEstimator' block. #732)
• [gym/common] Allow negative block update period to match env step. ([gym/common] Allow negative block update period to match env step. #734)
• [gym/common|gym/toolbox] Promote generic SE3 math utilities from toolbox to common module. ([gym/envs] Fix broken 'Ant' environment. #731)
• [gym/envs] Fix broken 'Ant' environment. ([gym/envs] Fix broken 'Ant' environment. #731)
• [misc] Update documentation. ([misc] Add documentation. #736)