Remove ChangeLog files. Superceded by git history logs.
Make sure to install the Lang melting-point descriptor.
Merge branch 'master' of github.com:openbabel/openbabel
Make sure to remove the generated openbabel-ruby.txt temporary file.
Work around bugs in Clang/LLVM libc++ which ships with Mac 10.9.
Make sure to check for OBUnitCell before dereferencing.

Bug found via Clang static analysis checker.