smarts queries run faster (like vector bindings). Though there is an addition to the smarts parser
exposed here, I do not recommend using it in client code.
instead of using the property map interface.
A nice side-effect is that the wart of having to use property maps to loop over bonds or atom neighbors
is now gone.
This potentially breaks lots of client C++ code.
http://sourceforge.net/tracker/index.php?func=detail&aid=1968930&group_id=160139&atid=814650
In order to fix the problem, the value of the query function for atomMass queries
is being multiplied by a constant factor (currently 1000) before converting
to an int. This allows distinguishing between things like [CH4] (where the
C has mass 12.011) and [12CH4] (where the C has mass 12.000).
