Joints: cam and follower coupling (joint.cam) (#1734)

Thanks @SychPL.

assets/locales/en.json

@@ -295,6 +295,13 @@
   "browser.precision": "Precision: {precision}",
   "browser.sketch_name": "Sketch{number}",
   "browser.units": "Units: {units}",
+  "cam.flat": "Flat face",
+  "cam.follower": "Follower",
+  "cam.knife": "Knife edge",
+  "cam.needs_joints": "needs a joint that turns and one that slides or swings",
+  "cam.roller": "Roller",
+  "cam.roller_pick": "Roller (optional)",
+  "cam.tip_pick": "Tip (optional)",
   "cmd.appearance_assign": "Appearance",
   "cmd.appearance_library": "Appearance Library",
   "cmd.appearance_list": "List Appearances",
@@ -398,6 +405,7 @@
   "cmd.inspect_minimum_radius": "Minimum Radius Analysis",
   "cmd.inspect_zebra": "Zebra Analysis",
   "cmd.joint_as_built": "As-Built Joint",
+  "cmd.joint_cam": "Cam",
   "cmd.joint_create": "Joint",
   "cmd.joint_delete": "Delete Joint",
   "cmd.joint_drive": "Drive Joints",