Minor updates to metabolic example package

[jimmyDunne]

PR addresses address' #102 with a minimum set of changes that allows the Metabolics tutorial to be completed. I am performing a tutorial refactoring in #104, but those changes won't be finished before the release.

Changes made

Cmake changes for building the file tree for the example. Models, tutorial files, and data have been placed such that the example can be run without error. The CMC setup files, External Loads setup file, and experimental data are in the top directory because of issues OpenSim has with paths to files.

Updats to the scripts were performed in #103

Tests that I have completed

• Built locally to ensure that the CMake changes build the directory structure.
• Run through the example using the locally build directory to check that the setup files work as is and that the scripts generate the correct outputs.

To be completed

• Once reviewed, I will update the tutorial instructions to use the local files (rather than downloading a folder of scripts.

[chrisdembia]

I pushed a commit to fix indentation in CMakeLists.txt.

We might have fixed the paths issue such that the files no longer need to be rearranged (opensim-org/opensim-core#2366), though I am still fine with this new organization.

It would be good to also delete the duplicate scripts from the GUI (in a separate PR).

[jimmyDunne]

You're the best!!