Use D0 dangling energy model
Squashed 'gtfold/' content from commit cd56b6f

git-subtree-dir: gtfold
git-subtree-split: cd56b6fe2f59de54953f1e7367216734bc62b01e
Merge commit '9e200b2458dc833ca0bf0d5068de38fa52d54f43' as 'gtfold'
Implement SWIG-based Python wrapper for gtmfe
Add temporary energy print for debugging
Remove cruft from init_fold
Remove cruft from free_fold
Remove unnecessary calculate_mfe method
Remove cruft variables from mfe_main
Set up PolytopeVector struct to hold results
Remove "thread count" printout
Compute polytope vector during trace()
Trim down signature of readThermodynamicParameters
Port MFE algorithm to float arithmetic
Port traceback algorithm to float arithmetic
Set up parameterization in GTMFE
Set default values for GTMFE parameters
Use SWIG-based GTMFE in iB4erunner
Remove leftover energy-printing line
Drop many unneeded files in GTfold directories