moved ifdef outside functions to avoid gcc errors
don't free pointers if there aren't active impropers, torsions, etc.
Merge free changes
read atom name when reading pdb without par
correct order in calloc
initial version of sdf reader
convert sdf v2000 to use sscanf
store atom group name in sdf
make sure atom_group_name is well-trimmed and happy
free atom group name in full free
do not expose v2000/v3000 functions
streaming version of the sdf reader
whitespace cleanup
+ testing out travis CI
- removing compiling with clang, as it doesn't support nested
  functions which are required for rmsd.c
Merge Structural Bioinformatics Lab changes