inchi 1.04: New formula

InChI generation library and command line tool.
open-babel 2.3.2

This formula is based on the open-babel formula in the main homebrew repository. Changes:

- Added HEAD option
- Depend on separate inchi install instead of using bundled inchi library
- Skip patches if installing HEAD
- Automatic path detection for InChI and Cairo is fixed after 2.3.2
- DRUN_SWIG cmake option required for python and java language bindings
- Only print java bindings caveat if building with java