merge confab into openbabel
Merge branch 'confab' of https://github.com/cowsandmilk/openbabel into confab
Porting commits from the original Confab:

torlib.txt, rotor.cpp:
* Using Graph Symmetry, remove symmetrical torsions.
* Reduce the torsions by incorporating graph symmetry. Note that torlib.txt trumps this in the case of CX3 where X is a halide
* Force Forcefield setup always. IsSetupNeeded() fails silently in some cases
Remove confsearch.h. Unused.
Add basic test for QCP align.
Turn confab into an Op.
Add confabreport output format used to replace 'calcrmsd' executable in original Confab. Tidy up opconfab code, and suppress writing out of the original molecule.
Final changes to make confab ready for merging:
1. Revert changes to IsSetupNeed() as asked by Geoff
2. Remove calcrmsd and confab executables
Merge branch 'master' into confab
Merge branch 'master' into confab