It's not missing - it's just not in the same spot that it used to be, and the new release doesn't seem to have a proper setup in place for calling bitbake directly. I could be mistaken - I haven't spent that much time trying to figure it out, and the documentation is not updated.
If you look at the BSP User's Guide for the previous release, section 3 (Building an Intel Edison image with make), those instructions should still work, as the makefiles have been updated to use the poky scripts at their new location. If you look through the top level makefile, you will find the path to the poky tools.
Hope this helps,
Use the bsp guide from here: Intel® Edison Products — Board Support Package (BSP) User Guide.
There are now to ways to build the firmware image: Bitbake and Make. Bitbake builds are covered in section 2 and Make builds are covered in section 3.
For Bitbake builds after completing the steps in section 2 you can build an individual recipe directly in the same directory that was used in section 2 step 5.
For Make builds after completing the steps in section 3 you can build an individual bb recipe directly in the following directory: <SOURCE ROOT>/out/current/build. For example after 'make image' completes, 'cd ../out/current/build'; 'bitbake mdns -c clean';