[ImuFactor] tangent space Imu Factor

Don't bother reviewing this yet

At the moment, most of the work was done here by Hayk Martiros.
However, while moving changes around, it proved practical to
lose track of the original commit.

Topic: tangent_space_imu_factor
Relative: on_manifold_imu_factor_test
Labels: draft

Author: bradley-solliday-skydio

dev_requirements.txt

@@ -80,6 +80,8 @@ fonttools==4.38.0
     # via matplotlib
 graphviz==0.20.1
     # via symforce (setup.py)
+gtsam==4.1.1 ; python_version < "3.10"
+    # via symforce (setup.py)
 idna==3.4
     # via requests
 imagesize==1.4.1
@@ -190,6 +192,7 @@ numba==0.56.3 ; python_version < "3.11"
 numpy==1.23.4
     # via
     #   contourpy
+    #   gtsam
     #   matplotlib
     #   numba
     #   pandas
@@ -251,6 +254,7 @@ pylint==2.15.5
     # via symforce (setup.py)
 pyparsing==3.0.9
     # via
+    #   gtsam
     #   matplotlib
     #   packaging
 pyrsistent==0.19.1