c_api and julia wrapper

[HiroIshida]

comparison with corresponding python script:
julia : 1.15 [sec]
python: 3.23 [sec]

import _tinyfk as tinyfk
fksolver = tinyfk.RobotModel("../data/fetch_description/fetch.urdf")
link_names = [
    "l_gripper_finger_link", 
    "r_gripper_finger_link", 
    "wrist_flex_link",
    "wrist_roll_link",
    "shoulder_lift_link",
    "upperarm_roll_link"]

joint_names = [
    "torso_lift_joint",
    "shoulder_pan_joint",
    "shoulder_lift_joint",
    "upperarm_roll_joint",
    "elbow_flex_joint",
    "forearm_roll_joint",
    "wrist_flex_joint",
    "wrist_roll_joint"]

av = [-0.4]*8
av_seq = [av]

joint_ids = fksolver.get_joint_ids(joint_names)
link_ids = fksolver.get_link_ids(link_names)

# returining poses and jacobian 
rot_also = False
base_also = False
import time 
ts = time.time()
for i in range(1000000):
    P, J = fksolver.solve_forward_kinematics(av_seq, link_ids, joint_ids, 
            rot_also, base_also, False)
print(time.time() - ts)