1) Read charges from cif file and add it to special OBPair.

2) New Function in OBPairTemplate GetGenericValueDef(const ValueT &def_val).
Return specified default value if the data is not exist.
Added support for old version of GLIBC
Merge branch 'GLIBC24'
New gitignore
Merge branch 'master' of git://github.com/openbabel/openbabel

Conflicts:
	src/formats/cifformat.cpp
Assert in cifformat excluded.
Merge pull request #17 from orex/master

Read charges from CIF. New Function in OBPairTemplate to give default parameter.